Syrian activists say death toll in blasts at Aleppo University rises to 87

In this photo released by the Syrian official news agency SANA, Syrian people gather at the site after an explosion hit a university in Aleppo, Syria, Tuesday, Jan. 15, 2013. Two explosions struck the main university in the northern Syrian city of Aleppo on Tuesday, causing an unknown number of casualties, state media and anti-government activists said. There were conflicting reports as to what caused the blast at Aleppo University, which was in session Tuesday. (AP Photo/SANA) (The Associated Press)

In this photo released by the Syrian official news agency SANA, Syrians stand in rubble of the damaged university building caused by an explosion in Aleppo, Syria, Tuesday, Jan. 15, 2013. Two explosions struck the main university in the northern Syrian city of Aleppo on Tuesday, causing an unknown number of casualties, state media and anti-government activists said. There were conflicting reports as to what caused the blast at Aleppo University, which was in session Tuesday. (AP Photo/SANA) (The Associated Press)

Anti-regime activists say the death toll in two big explosions on the campus of a Syrian university has risen to 87.

The Britain-based Syrian Observatory for Human Rights said Wednesday that the number of those killed in the blasts at Aleppo University could rise even further because medics have collected more unidentified body parts and some of the more than 150 injured are in critical condition.

It remains unclear what caused the Tuesday blasts, whose aftermath was documented in videos posted online and shown on Syrian state TV.

Anti-regime activists accused forces loyal to President Bashar Assad of launching airstrikes on the campus. The state news service said a "terrorist group" fired missiles.

The U.N. says more than 60,000 people have been killed since Syria's conflict began in March 2011.