Police investigators claim to have made a breakthrough on the armed attack on a bus in Pakistan's Karachi city that claimed 46 lives, a media report said on Monday.
At least 46 people were killed in the attack on May 13 when gunmen opened indiscriminate fire inside a bus carrying people of the Shia Ismaili community.
"Four suspects have been detained on charges of their involvement in the killings of Shia Ismaili community members," said a senior police officer who is a member of the high-level probe body formed by the Sindh inspector general of police, Dawn online reported.
The officer said that they considered the arrest of the four suspects as a significant development in the investigation, which might help them ascertain the identity and motive of the attackers.
On insistence about the possible affiliation of the held suspects, the police officer said that "all I can share at this moment is that they are militants who belonged to a banned outfit".