NATO officials say five Polish soldiers have been killed in a roadside bomb attack in eastern Afghanistan, marking the deadliest single attack of the Afghan war for the coalition member. Local Afghan officials said an improvised explosive device went off Wednesday near the convoy of troops in Ghazni province. The Taliban immediately claimed responsibility.

Meanwhile, The Associated Press quoted members of Poland's opposition as renewing their call for an immediate pullout of Poland's 2,600 troops. Poland is scheduled to withdraw all of its combat troops by 2014.

Earlier Wednesday, Afghanistan's defense ministry said that it is making progress in training security forces ahead of the expected 2014 withdrawal of foreign combat troops.

Defense Ministry spokesperson Mohammad Zahir Azimi said the number of Afghan National Army troops now stands at 180,000. The United States and NATO say they would like to see 195,000 Afghan troops in the field by October of 2012.

International forces already have begun handing over security responsibility to Afghan forces ahead of the 2014 withdrawal.

Separately, Afghan police said Wednesday they shot and killed a would-be suicide bomber before he could detonate his explosives outside a bank in the eastern province of Khost, a stronghold of the al-Qaida-linked Haqqani militant network.

It is not immediately clear whether the bomber was targeting the bank or a nearby police station. Police also are looking for a possible second attacker who escaped.