21 dead and 25 injured in Baghdad suicide bombing.

According to a police source with knowledge of the incident speaking to CNN by phone, a suicide bombing occured in a predominately Shia area of Baghdad which left 21 people dead and 25 people injured.

The bomber targeted a Shia mosque in the city's northeast al Harithyia neighborhood,

there has been no claim of responsibility, as of yesterday

The past few weeks have seen a series of car and suicide attacks on Shia targets, some of which have been claimed by ISIS.

Although Baghdad's perimeter has appeared to hold firm against ISIS encroachment, the militant Sunni group has made strategically valuable gains in the country's Anbar province, west of the capital.

ISIS, which calls itself the Islamic State, has been accused of massacring Shiites in areas it controls.