Pakistan holds day of mourning after university attack

Pakistani women light candles during a vigil for victims of the Bacha Khan University attack, Wednesday, Jan. 20, 2016 in Peshawar, Pakistan. Taliban gunmen stormed a university in northwestern Pakistan on Wednesday, killing many people and triggering an hours-long gun battle with the army and police before the military declared that the assault in a town near the city of Peshawar was over. AP

CHARSADDA, Pakistan — Pakistan is observing a day of mourning after a deadly attack by Islamic militants who stormed a northwestern university the day before, gunning down students and teachers and spreading terror before the four gunmen were slain by the military.

The death toll from the assault at Bacha Khan university in the town of Charsadda rose to 21 on Thursday, after another student died in hospital, according to police official Tariq Khan.

READ: 19 killed in university attack in Pakistan

Flags on official buildings and the parliament are flying at half-staff and police have stepped up security at schools and educational centers across the country.

A breakaway Taliban faction took responsibility for the university attack, which raised grim echoes of the 2014 school massacre that left 150 dead, 144 of them children.