(Adds fighter jet fired on over Mosul, Tal Afar fighting) * Fighting spreads to **rthwest town near Syria border * Pictures appear to show ISIL fighters shooting dozens * Nine killed in Baghdad suicide bombing By Ziad al-Sanjary and Ahmed Rasheed MOSUL/BAGHDAD, June 15 (Reuters) - The insurgent offensive that has threatened to dismember Iraq spread to the **rthwest of the country on Sunday, when Sunni militants launched a dawn raid on a town close to the Syrian border, clashing with police and government forces. As the rapid advance south by the Islamic State in Iraq and the Levant (ISIL) towards Baghdad appeared to slow over the weekend, fierce fighting erupted in the town of Tal Afar 60 km (40 miles) west of Mosul near the Syrian border, security sources and a local official said.