BAGHDAD (AP) — Iraq's government-sanctioned paramilitary forces, made up mainly of Shiite militiamen, launched a new push Wednesday to capture villages west of the city of Mosul from Islamic State militants, officials said.

The forces' spokesman, Ahmed al-Asadi, said on Wednesday that the villages being targeted are located southwest of the town of Tal Afar, still held by the Islamic State group. The spokesman for the Hezbollah Brigades, Jaafar al-Husseini, said the troops captured the villages of Sharia and Khirbat al-Jahish.

A car bomb exploded near the advancing forces, killing three troops and wounding 14 others, al-Hussaini added. At least 17 IS militants were killed in the fighting, which was still underway late Wednesday afternoon, he said.

The move by the umbrella group of mostly Shiite militias known as the Popular Mobilization Forces is likely coordinated with government efforts to recapture the western part of Mosul from IS. Iraqi government forces this week took a strategic southern hilltop area overlooking the Mosul city airport.

Mosul, which is now the last IS urban stronghold in the country, fell into the hands of the extremists in the summer of 2014, during a shocking blitz that captured large swaths of northern and western Iraq. The battle for Mosul, backed by the U.S.-led coalition, has already driven the militants from the eastern half of the city, which is divided roughly in half by the Tigris River.

The Shiite militias already hold a small airport outside Tal Afar, which is s located some 93 miles (150 kilometers) east of the Syrian border.