KABUL, Afghanistan - Afghan security forces shot dead a would-be bomber Monday outside the venue for a meeting of regional leaders and tribal powerbrokers starting in Kabul later this week, the Afghan government said.

The man was carrying a bomb in a box close to the entrance to the site where the meeting will be held, but was shot before he could detonate the explosive, Interior Ministry spokesman Sediq Sediqi said. Two accomplices were arrested, the Afghan intelligence service said in a statement.

The traditional meeting, called a Loya Jirga, is expected to include about 2,000 participants from all over the country who will discuss ongoing negotiations for a future U.S.-Afghan strategic partnership agreement and efforts to reconcile with the Taliban.

Previous such meetings have been targeted by militants, and Afghan insurgents appear to be trying to shake the confidence of would-be attendees.

The Taliban said on Sunday that they had obtained the Loya Jirga's security plans, emailing images to reporters. The Afghan government and NATO officials said the document was a forgery.

The Interior Ministry argued that the Talian created a fake document to try to scare Afghans who are planning to attend the conference. The Taliban boasted in a statement that maps and documents they have obtained will allow them to launch precision attacks on the meeting.

NATO forces spokesman Lt. Col. Jimmie Cummings said that they do not believe it is genuine, and that a signature on the circulated document supposedly belonging to Lt. Gen. Curtis Scaparotti, the deputy commander of U.S. forces in Afghanistan, does not resemble Scaparotti's actual signature.

Meanwhile, the Taliban accused the Afghan government of spreading false reports of its own with the announcement that they had arrested a prominent spokesman for the insurgency.

The government said that it was confident that the man police arrested in Sar Hawza district of Paktika province was Zabiullah Mujahid, one of a handful of top spokesmen for the insurgent group.

"We strongly believe it's Zabiullah. Initial investigation shows he is Zabiullah Mujahid," Sediqi said. Afghan police have handed the man over to the Afghan intelligence service for further investigation, he said.

The name Zabiullah Mujahid has been used by multiple Taliban spokesmen over the years, but for the past couple years there has been one primary "Zabiullah" who most commonly answers the phone number used by journalists.

The Associated Press reached this man Monday afternoon by phone and he said he had not been captured.

"It is the propaganda of the Afghan government," Mujahid said. "This morning I heard the media reports that I had been arrested. It is not true." He said he was talking from eastern Afghanistan.

The conflicting claims over the arrest and the security plans show the increased importance of the propaganda side of the war. Both sides want to show that they are on the verge of winning, ahead of scheduled withdrawals of NATO forces that could dramatically change the balance of power in the country and may have many Afghan powerbrokers rethinking their alignment.

As the two sides jockey for public opinion, daily violence continues to take lives. In the latest NATO death, a service member was killed Monday in an insurgent attack in the east, the military coalition said without giving further details. At least 11 international service members have been killed in Afghanistan so far this month.

On Sunday morning, a man captured during an operation nearly three weeks ago died in detention, the U.S. military said.

U.S. Central Command said in a statement that the detainee had been receiving medical care since he was taken on Oct. 25 in Kunar province. No details were given about his injuries or ailments. He had been held at a detention facility adjoining Bagram Air Field north of Kabul.

The statement said the man died after displaying "serious medical symptoms." The military said all efforts were taken to save his life and his remains are being handled according to Afghan and religious customs.

An investigation has been opened into the death, a move that the U.S. military said is normal procedure for the deaths of detainees in their care.