Updated

Syrian activists say the death toll in two blasts inside the campus of the main university in the northern city of Aleppo has risen to 83.

The Britain-based Syrian Observatory for Human Rights says some of the more than 150 injured in Tuesday's blast are in critical condition.

It says the dead included university students and civilians staying in the university dormitories after being displaced by fighting between forces loyal to President Bashar Assad and rebels seeking to topple his regime.

It's unclear what caused the explosions, with each side blaming the other.