After the Liberation Tigers of Tamil Eelam broke off the peace negotiations with the government with the 1990 massacre of Sri Lankan Police officers, they took over police stations and launched an offensive against unprepared military units in the North-East, taking over large swathes of territory from undermanned army units consisting of volunteers while professional troops were sent to the south to quell the JVP uprising.

[1][3][2] The operation started with Sri Lankan Army securing Kayts Island in late August, 1990 with a combined amphibious and airbone force.

The operation to transport troops across the lagoon commenced in the early hours of 13 September with use of Sri Lanka Navy fibreglass dinghies under heavy fire by the LTTE.

Gotabhaya Rajapaksa later commented that the Sri Lankan Army would have succeeded in its efforts if troops had crossed the lagoon immediately after securing Mandaitivu Island but delaying the crossing by over two weeks resulted in the failure to exploit an opportunity created by the disarray in LTTE forces due to the fall of Mandaitivu.

[3][2] Food and supplies were brought to the Fort for the operation by the troops of the 1 Special Forces led by Captain Fazly Laphir in a mission dubbed "Suicide Express".

Many other Army officers such as Kamal Gunaratne, Mahesh Senanayake, Shavendra Silva who made large contributions during the final phase of the Sri Lankan Civil war also took part in the operation in different capacities.