a suicide bomber first attacked the convoy before militants opened fire , killing the brigadier general hassan abbas toufan , the commander of the iraqi first division , a member of the division and an intelligence officer said .
a colonel and two lieutenant colonels also died in the attack in the nadhem al-taqseem region , north of fallujah in the anbar province yesterday .
fighting has been focused on the provincial capital of ramadi , where the government had been making slow progress .