The No.2 leader of the Islamic State (IS) terrorist group is believed to have been killed on Wednesday in a US-led coalition airstrike in northern Iraq, the Iraqi defense ministry said."Based on accurate intelligence reports, the US-led coalition carried out an airstrike on the second man of Daesh (IS in Arabic) terrorist gang's Abu Ala Afri, and a large number of members of the criminal gang while they were holding a meeting at al-Shuhadaa mosque in the town of Tal Afar," the ministry said in a statement.The attack occurred in the IS-held town of Tal Afar, some 70 km west of Nineveh's provincial capital Mosul, which itself is some 400 km north of Iraq's capital Baghdad, Xinhua news agency reported.Earlier, unconfirmed reports claimed that top IS leader, Abu Bakr al-Baghdadi, was believed to have been severely injured in an airstrike, and that Abu Alaa al-Afri was the temporary leader while Baghdadi recovered from his wounds.