Islamic State group seizes town in Iraq's Anbar province

This picture released on Thursday, May 21, 2015 by the website of Islamic State militants, shows damaged Syrian military helicopters at Palmyra air base that was captured by the Islamic State militants after a battle with the Syrian government forces in Palmyra, Syria. Activist and officials say members of the Islamic State group are conducting search operations in the ancient town of Palmyra where they have detained and killed dozens of people. (The website of Islamic State militants via AP) (The Associated Press)

This picture released on Thursday, May 21, 2015 by the website of Islamic State militants, shows a bunker with a heavy machine gun mounted on its top at Palmyra air base that was captured by the Islamic State militants after a battle with the Syrian government forces in Palmyra, Syria. Activist and officials say members of the Islamic State group are conducting search operations in the ancient town of Palmyra where they have detained and killed dozens of people. (The website of Islamic State militants via AP) (The Associated Press)

This picture released on Thursday, May 21, 2015 by the website of Islamic State militants, shows the Tadmur prison in the Syrian town of Palmyra that was captured by the Islamic State militants after a battle with the Syrian government forces, Syria. Activist and officials say members of the Islamic State group are conducting search operations in the ancient town of Palmyra where they have detained and killed dozens of people. (The website of Islamic State militants via AP) (The Associated Press)

A tribal leader says Islamic State militants have seized another town in Iraq's western Anbar province, less than a week after capturing the provincial capital, Ramadi.

Sheikh Rafie al-Fahdawi said Friday that the small town of Husseiba fell overnight. He says police and tribal fighters withdrew after running out of ammunition.

Husseiba is about seven kilometers (four miles) east of Ramadi, where IS militants routed Iraqi forces in their most significant advance in nearly a year.

The Iraqi government plans to launch a counteroffensive in Anbar involving Iranian-backed Shiite militias, which have played a key role in rolling back the IS group elsewhere in the country. The presence of the militias could however fuel sectarian tensions in the Sunni province, where anger at the Shiite-led government runs deep.