London: A man shot dead by the Scotland Yard after he went on a stabbing frenzy on a busy high street in south London was a convicted Islamist terrorist, with family links to Sri Lanka, who was recently released from prison after serving half of his sentence period for preparation of acts of terrorism, police said.

The Metropolitan Police said Sudesh Mamoor Faraz Amman, a 20- year- old British national with extended family in Sri Lanka, had pledged allegiance to the Islamic State ( ISIS).