(Adds Pakistan comment, background)
By Rob Taylor
FORWARD OPERATING BASE LIGHTNING, Afghanistan, July 8 (Reuters) - Insurgents have stepped up operations in Afghan border provinces close to Pakistan, one of Afghanistan's top generals said, with militant numbers up on last summer as government forces work to improve security in the volatile east.
Major-General Mohammad Sharif Yaftali, who commands Afghan forces in seven crucial southeast provinces, said insurgent numbers were up around 15 percent on last year's summer fighting months, with an estimated 5,000 insurgents now in his area.
Many were Pakistanis and Chechens, Yaftali said, reinforcing recent assessments by Afghan army chief of staff General Sher Mohammad Karimi that the insurgency's backers in Pakistan had shut Islamic schools to send more fighters across the border.
"They closed them on purpose, to push them to Afghanistan to disrupt security," said Yaftali. "There are 3,500 madrassas in Pakistan and if every one send five people, well, you can imagine."
Pakistan, which supported the 1996-2001 Taliban government in Afghanistan, is seen as crucial to U.S. and Afghan efforts to promote peace in Afghanistan, a task that is gaining urgency as NATO-led combat troops continue to leave the country.
Karimi, in comments rejected by Islamabad, said in a recent interview that the influential Pakistan military could end the 12-year-old Afghan war if it chose to "in weeks", despite facing a Taliban insurgency of its own.
Afghanistan has levelled a string of accusations against Pakistan since peace talks with the Taliban imploded last month, in a row that has dashed hopes of a reset in the relationship between the South Asian neighbours.
Kabul is angry with what it sees as the insurgent movement's attempt to position itself as a legitimate government in waiting and has accused Pakistan of supporting and sheltering militants.
Pakistan, for its part, is upset because it feels it played a crucial role in bringing the Taliban to the negotiating table. On Monday, Foreign Office spokesman Aizaz Ahmad Chaudhry said accusations that it was shutting schools to send fighters to Afghanistan were baseless.
"We have checked. This information is not correct. Pakistan wants what is best for peace and stability in the region," he said, declining further comment.
Yaftali said recent security operations in the east by four Afghan brigades had greatly improved security with only minimal assistance from NATO coalition allies. Major roads were cleared and more than 650 insurgents killed over three months.
While local people in Paktia province say the Taliban-allied Haqqani network still influences at least five of 14 districts, Yaftali said around 150,000 girls attending school in his command were proof the insurgency was on the back foot and its leaders were now throwing everything possible into the fight.
As evidence, Afghan commanders organised a media conference with a Pakistani insurgent captured after being shot in the leg and who was handcuffed to a bed as he recovered at the military's Paktia Regional National Hospital.
"The people told us there are infidels and to go and fight against them. That's why I came," said the fighter, who gave his age as around 22 and his name as "Hezbollah", after the Lebanon-based Islamic militant group and political bloc.
Hezbollah, captured with a radio and AK-47 rifle and whose name is unlikely to be genuine, said he had received minimal training and was the youngest of a group of 13 fighters who had made their way over the mountains into Afghanistan, staying for 15 days before being shot.
"The people did not help us. But there was a mosque and that was like our base station. We had food and water and sleep," he said. "I don't know where I was captured, because I am not from this country. We were ambushed."
Rapid improvements in the ability of the army to operate independently of NATO forces has raised hopes among coalition commanders that Afghan security forces will be able to match the insurgency after the 2014 exit of most Western troops.
Paktia is one of three provinces fiercely contested by the militant Haqqanis, blamed for several prominent attacks in Kabul and elsewhere in Afghanistan.
The province, while less violent than neighbouring Paktika and Ghazni provinces, in a frequently used insurgent run on the approach to the capital Kabul due to its areas of thick forest and rugged mountain terrain.
The Taliban and their allies have also been accused there of shutting down girls' schools, as in many other provinces of the still deeply conservative and male dominated country.
Yaftali said foreign insurgents, often used to coordinate and lead anti-government operations, were increasingly ill-trained, despite being pushed out in greater numbers across the border to face improving Afghan troops and police.
"We used to get involved in some tough fights," he said, referring to his 19,000 soldiers of the Afghan army's 203rd Thunder Corps. "Now all the highways are open. We have focused on the insurgent leaders." (Additional reporting by Mehreen Zahra-Malik and Maria Golovnina in ISLAMABAD; Editing by Nick Macfie)