A rights group is accusing combatants in Libya of committing "unlawful" attacks against civilians in the capital Tripoli that could amount to war crimes.

Amnesty International says in a statement Thursday that several residential areas in southern Tripoli were attacked with inaccurate weapons between April 13-17. Based on witnesses and satellite images, Amnesty concluded there was no evidence of any military targets in these areas but could not conclusively identify the attackers.

Field Marshal Khalifa Hifter's self-styled Libyan National Army launched an operation to retake the capital on April 4 and has been locked in heavy fighting in and around the city with militias loosely allied with a U.N.-supported government based there.

The statement says most interviewees from the area blamed the LNA forces.