Pakistan journalists chanting slogans "Killer, killer, government killer!," during a protest rally in front of Supreme Court to condemn the killing of a photo journalist Hayatullah Khan

Hundreds of Pakistani journalists and lawmakers have taken part in mass demonstrations in the capital and around the country to protest the recent killing of a local reporter. The protesters are demanding a government investigation into the death, as allegations mount that the journalist, Hayatullah Khan, was kidnapped by Pakistan's secret intelligence agencies.

Pakistani journalists gathered in front of the country's national parliament to demand the arrest of 30-year old Hayatullah Khan's killers.

Khan's battered and handcuffed body was found Friday outside his hometown of Mir Ali, not far from the Afghan border.

Khan was kidnapped more than six months ago in Pakistan's troubled North Waziristan tribal area, where Pakistani troops are fighting suspected Taleban and al-Qaida militants.

He disappeared just days after reporting on a controversial attack on a suspected terrorist hideout that killed al-Qaida operative Abu Hamza Rabia.

The government initially claimed Rabia died while making explosives, but Khan produced photographs of U.S. missile fragments in the area and suggested American forces carried out the attack from neighboring Afghanistan. The alleged missile strike sparked massive anti-American and anti-government protests throughout Pakistan.

The government is denying allegations that its secret agencies were behind Khan's kidnapping and murder.

Interior Minister Aftab Sherpao says an official investigation into the killing is underway.

The minister says it is likely Khan was killed by local militants, and notes a number of government soldiers and allied tribesman have also been murdered in recent months.

But local reporters say the government's response is too little, too late. They say the government failed to protect Khan, failed to secure his release and is now only half-heartedly looking for his killers.

The reporters want the investigation handed over to the country's Supreme Court.

Pakistani journalists called for a national day of mourning. Press groups are also boycotting government news conferences and refusing to cover official events, including an ongoing budget session in the national parliament, until their demands are met.

Khan was one of at least three other local journalists killed in the tribal areas since the government launched its military campaign against Islamic extremists alleged to be hiding there.