BAGHDAD, Sept 25 (Reuters) - A suicide bomber blew himself up in a commercial street of Baghdad on Sunday, killing seven and wounding 28, according to police sources.

The explosion happened in Iskan, a mostly Shi'ite district in the west of the Iraqi capital.

Islamic State has stepped up bomb attacks in government-held areas this year as it loses territory to U.S.-backed Iraqi forces and Iranian-backed Shi'ite militias.

The hardline Sunni group continues to control vast areas in northern and western Iraq, including the city of Mosul, captured in 2014.

(Reporting by Kareem Raheem in Baghdad; Writing by Maher Chmaytelli in Paris; Editing by Mark Potter) ((maher.chmaytelli@thomsonreuters.com; +9647901917030;))