Updated

The British envoy to India says his country regrets a massacre of hundreds of Indians by British colonial forces in the northwest city of Amritsar 100 years ago and "will continue to do so."

Saturday marks the centenary of the attack at Jallianwala Bagh by British colonial troops against unarmed Indians attending a peaceful rally calling for independence.

More than 300 Indians were killed and 1,200 injured during the massacre, which galvanized the national independence movement.

British High Commissioner Dominic Asquith says "the revulsion that we felt at the time is still strong today," as he paid tributes at the Jallianwala Bagh memorial in Amritsar.

British Prime Minister Theresa May on Wednesday called the killings a "shameful scar" in British-Indian history but stopped short of formally apologizing.