Pakistani authorities say police in the southern port city of Karachi have arrested two al-Qaida militants for their involvement in a suicide attack earlier this year that killed a U.S. diplomat.

The police chief for the Sindh province Jehangir Mirza says the suspects were captured during an early morning Monday raid.

The blast near the U.S. consulate in Karachi on March 2 killed the U.S. diplomat David Foy, three Pakistanis and the attacker who rammed his explosive-laden car into a car carrying the diplomat. More than 50 people were wounded in the attack, including a Moroccan child.

Last week, Pakistani intelligence officials arrested six people in connection with the attack and identified the suicide bomber. Authorities said the six were associated with the suicide attacker, and that they were linked to al-Qaida, as well as banned domestic militant groups.

Some information for this report was provided by AP and Reuters.