Exhibit 99.1

FOR IMMEDIATE RELEASE
Wednesday, October 18, 2000


CONTACTS:
Investor Relations                        Media Relations
J. Brad McGee                             Judith Czelusniak
Executive Vice President,                 Senior Vice President,
Chief Strategy Officer                    Corporate Relations
Tyco International (US) Inc.              Tyco International (US) Inc.
(603) 778-9700                            (561) 988-7424


                     TYCO COMPLETES PURCHASE OF MALLINCKRODT

          Acquisition Will Have Immediate Positive Impact on Earnings;
       Strengthens Tyco Healthcare's Leading Positions in Medical Devices

Pembroke, Bermuda, October 18, 2000 - Tyco International Ltd. (NYSE: TYC; LSE:
TYI; BSX: TYC), a diversified manufacturing and service company, today announced
that it has completed the acquisition of Mallinckrodt Inc. Under the terms of
the merger agreement, Mallinckrodt shareholders will receive .9384 shares of
Tyco common stock for each share of Mallinckrodt owned. The transaction is
valued at approximately $4.2 billion. Mallinckrodt, which had 1999 revenues of
$2.6 billion, has major positions in respiratory care, diagnostic imaging and
analgesic pharmaceuticals.

"The Mallinckrodt acquisition will be immediately accretive to Tyco's earnings,"
according to L. Dennis Kozlowski,  Tyco's Chairman and Chief Executive  Officer.
"It offers  consolidation  opportunities  as well as significant  manufacturing,
purchasing and distribution synergies.  Our past acquisitions in Tyco Healthcare
have achieved strong top line growth and operating efficiencies. The acquisition
of   Mallinckrodt   also  will  provide  ongoing   positive   benefits  to  Tyco
shareholders.

"Tyco has a strong  history of success in building  leadership  positions in the
healthcare  industry.  Tyco  Healthcare  has  grown  to be a  powerful  force in
disposable medical supplies and medical devices through previous acquisitions of
such industry brands as Kendall, United States Surgical, Auto Suture,  Sherwood,
Davis & Geck, Graphic Controls and ValleyLab. With the addition of Mallinckrodt,
Tyco  Healthcare  becomes  the  second-largest  manufacturer,   distributor  and
servicer  of  medical  devices  worldwide,  and the  leader  in  bulk  analgesic
pharmaceuticals," Mr. Kozlowski stated.



This  acquisition  makes Tyco  Healthcare  the leader in the fast growing global
respiratory care arena, with products such as Mallinckrodt  endotracheal  tubes,
Shiley tracheostomy tubes, Nellcor pulse oximeters, Puritan-Bennett ventilators,
and new  technologies  including  the recently  launched  OxiFirst  fetal oxygen
monitor  and  HELiOS  liquid  oxygen  system.  Mallinckrodt  also is a leader in
developing  new products in the growing  alternate  care markets for home oxygen
therapy,  sleep  therapy  and  portable  ventilation.   In  diagnostic  imaging,
Mallinckrodt   has  leadership   positions  in  imaging   contrast   agents  and
radiopharmaceuticals,  including Opitray and OptiMark.  Pharmaceutical  products
include  leadership  positions  in bulk  pharmaceuticals  and a rapidly  growing
dosage product line.

"The combined  strength of  Mallinckrodt's  products and Tyco's global sales and
service  organization  will allow Tyco Healthcare to leverage its  international
infrastructure  and enhance  penetration in key geographic  markets," stated Mr.
Kozlowski. "Mallinckrodt's strong positions in the respiratory,  pharmaceuticals
and diagnostic  imaging segments will provide Tyco with excellent  platforms for
future acquisitions and licensing agreements."

About Mallinckrodt
Mallinckrodt  is a global  manufacturer  and  distributor  of specialty  medical
products  designed to sustain  breathing,  diagnose  disease  and relieve  pain.
Mallinckrodt  does  business in more than 100  countries and had fiscal 1999 net
sales of $2.6 billion.  Mallinckrodt is the industry leader in respiratory  care
products, including those used for oxygen monitoring,  critical care ventilation
and  service  as well as  airway  management  disposables.  In  pharmaceuticals,
Mallinckrodt  is the number one  manufacturer  of bulk  narcotics and other drug
chemicals,  and is the world's largest  producer of  acetaminophen.  The growing
dosage pharmaceutical  segment is focused on pain management,  addiction therapy
and attention deficit hyperactivity disorder (ADHD).  Mallinckrodt also provides
laboratory and microelectronic  chemicals. Its imaging products include contrast
media used in x-ray, magnetic resonance imaging (MRI), computer axial tomography
(C-T) and ultrasound diagnostic procedures.  Mallinckrodt's radiopharmaceuticals
are used for diagnostic and therapeutic nuclear medicine procedures.

About Tyco International Ltd.
Tyco International Ltd. is a diversified manufacturing and service company. Tyco
is the world's  largest  manufacturer  and servicer of electrical and electronic
components  and  undersea  telecommunication  systems,  and the world's  largest
manufacturer,  installer and provider of fire protection  systems and electronic
security  services.  Tyco has strong leadership  positions in disposable medical
products,  plastics and adhesives,  and is the world's  largest  manufacturer of
flow control  valves.  Tyco  operates in more than 80 countries and has expected
fiscal 2000 revenues of $28 billion.



Forward-Looking Information
This release contains certain "forward-looking statements" within the meaning of
the Private  Securities  Litigations  Reform Act of 1995.  These  statements are
based on management's  current  expectations  and are subject to uncertainty and
changes  in   circumstances.   Actual  results  may  vary  materially  from  the
expectations  contained in the forward-looking  statements.  The forward-looking
statements in this release include  statements  addressing  future financial and
operating results and benefits of the acquisition.

The  following  factors,  among  others,  could cause  actual  results to differ
materially from those described in the forward-looking statements: the risk that
the businesses of Tyco and Mallinckrodt will not be integrated successfully, and
other economic, business, competitive and/or regulatory factors affecting Tyco's
and Mallinckrodt's businesses generally.

More  detailed  information  about  these  factors  is set forth in  Tyco's  and
Mallinckrodt's  filings with the Securities and Exchange  Commission,  including
Tyco's  Annual  Report on Form  10-K,  as  amended,  for the  fiscal  year ended
September  30, 1999,  Mallinckrodt's  Annual  Report on Form 10-K for the fiscal
year ended June 30, 1999, their most recent  Quarterly  Reports on Form 10-Q, as
amended,  and their Current  Reports on Form 8-K. Tyco is under no obligation to
(and  expressly   disclaims  any  such   obligation  to)  update  or  alter  its
forward-looking statements whether as a result of new information, future events
or otherwise.

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