The Taliban gunmen, who tried to kill Pakistani schoolgirl campaigner Malala Yousafzai in the country's restive northwest two years ago, have been arrested, the army said.

Militants boarded the teenage activist's school bus and shot her in the head in October 2012 for her outspoken views on girls' education, in an attack that also wounded two of her friends.

Malala survived and went on to earn international plaudits for her courageous and determined fight for all children to have the right to go to school.

The Tehreek-e-Taliban Pakistan (TTP) claimed the attack almost immediately but no arrests have been announced until now.

The detention of the 10 suspects involved the army, police and intelligence agencies and was part of the Pakistani military's ongoing offensive against the TTP and other extremist outfits.

"The group involved in the attack on Malala Yousafzai has been arrested," Major-General Asim Bajwa told a news conference.

Bringing the men to trial will likely be a long process - in Pakistan's sclerotic legal system, cases grind through the courts for years making little progress.

Bajwa said the group had a hitlist of 22 targets in addition to Malala, all ordered by the TTP's current leader Maulana Fazlullah.

All of its members were from Malakand, close to Mingora, the main town of Swat where Malala was attacked, he said. The leader Zafar Iqbal ran a furniture shop.

A spokesman for the TTP's new hardline Jamat ul Ahrar faction Ehsanullah Ehsan denied the military's claims.

"Three people were involved in that attack, one of them is martyred and two are alive," Ehsan said.

He denied the attack was ordered by Fazlullah - who is no longer recognised as TTP chief by Jamat ul Ahrar - saying it was planned by local militants.

On Twitter, he denied the arrests, saying the two surviving attackers were free.

After narrowly surviving the murder bid - one bullet grazed her brain and passed through her neck before lodging in her shoulder - Malala was taken to Britain with her family for treatment, where she now lives.

The TTP have said they will try again to kill her if she ever returns to Pakistan.

Her courageous recovery has made her a global figure - she won the EU's prestigious Sakharov human rights prize last year and was nominated for the Nobel Peace Prize.-Reuters