Ripudaman Singh Malik is on trial along with Ajaib Singh Bagri

Ripudaman Singh Malik and Ajaib Singh Bagri are accused of planting a pair of bombs on Air India jets in 1985.

One plane exploded over the Atlantic, killing 329 people. The second bomb killed two baggage handlers in Tokyo.

On Tuesday defence lawyers attacked the credibility of a key witness and said at least one defendant had no motive.

Beginning his summing up, lawyer David Crossin said a woman witness might have testified against Mr Malik simply because she was a disgruntled employee.

'False and profound'

He said the case rested on an obscure entry in her diary.

"We suggest the nature of that false evidence is profound," he said.

He said there was no evidence his client was even interested in Indian politics.

The prosecution alleges that the two men on trial, both Canadian Sikhs, put suitcase bombs onto planes in Vancouver with hopes of crashing the two jets.

They allegedly hoped to avenge the Indian government's attack on the Golden Temple in Amritsar in 1984.

Mr Bagri is alleged to have been a religious activist, urging fellow Sikhs in New York to "kill 50,000 Hindus".

Circumstantial

The trial has been the longest and most expensive ever mounted in Canada.

The case prosecutors presented in court is largely circumstantial, based mainly on testimony from people claiming either that the accused asked them to help plant the bombs or that they heard the suspects confess to the crime afterwards.

Both defendants deny the allegations outright.

These final arguments are expected to last several weeks.