BAGHDAD (Reuters) - At least 12 people were killed and 32 wounded early on Tuesday when a suicide bomber wearing a vest packed with explosives attacked a mosque in Abu Ghraib, about 25 km (15 miles) west of the Iraqi capital, police and medics said.

There was no immediate claim of responsibility for the blast, the first in or around Baghdad since the government declared victory over Islamic State militants in Falluja, further west, which was seen as a launchpad for such attacks.

Worshippers were gathered at the mosque, in a predominantly Sunni Muslim area, for prayers during the holy month of Ramadan during which the ultra-hardline militants have called on supporters to step up attacks.

(Reporting by Kareem Raheem; Writing by Stephen Kalin; Editing by Kevin Liffey)