A man and woman have been released from custody without being charged after days of questioning by French authorities investigating killings in southern France by a radical Islamist.

Seven people were killed in the attacks in March - Jewish schoolchildren, a rabbi and French paratroopers. Gunman Mohamed Merah was later killed in a shootout with police.

A man and woman were detained in southern France on Tuesday, the first arrests in the case since March.

Prosecutors say the man was freed Friday and the woman Wednesday, and that investigators are still searching for possible accomplices. The man was a convert to Islam who had lived in the same housing project as Merah.

Lawyers for the victims' families suspect Merah did not plan the killings alone.