13-year-old Mahin was on his way to a friend’s house when a speeding garbage truck hit him
Two lawyers, pro Awami League Rekha Akter and pro-BNP Saidur Rahman, received the same text message containing the threat on Sunday afternoon, Narayanganj lawyer's association chief Shakhawat Hossain said.
The Chittagong court had received similar threats earlier this month.
Court police's Inspector Habibur Rahman said they had beefed up security after receiving threats.
"We have taken the matter seriously," he said. "We've set up checkposts and letting people in after frisking them."