(Updates with suicide bomb in Helmand, previous Kabul)

By Abdul Qodoos

LASHKAR GAH, Afghanistan, Jan 31 (Reuters) - A suicide bomber killed a deputy provincial governor and at least five others in an attack in a mosque in southern Afghanistan on Thursday, officials said.

The attack, together with another suicide bombing in the capital Kabul earlier in the day, comes as two studies said Afghanistan risked reverting into a failed state and a haven for "terrorism" without new international efforts to win the war and bring economic development.

The deputy governor of Helmand province was among a congregation of men praying in a mosque in the provincial capital, Lashkar Gah, when the bomber struck.

"Five people including, Pir Mohammad, (the deputy governor) have been killed in this attack," Nisar Ahmad Barakzai, deputy head of the provincial public health department, told Reuters.

Provincial police chief Mohammad Hussein Andiwal said six people, including Mohammad, were killed and 18 worshippers wounded in the attack. The mosque is located opposite government offices in Lashkar Gah.

"When people stood up for prayer, the bomber approached the deputy governor and detonated his explosives," Andiwal told Reuters.

Earlier in the day, a suicide car bomber killed a civilian and wounded four others, including an army officer, in an attack aimed at an army bus in Kabul, officials said.

The Taliban carried out more than 140 suicide attacks last year. A spokesman for the group said a member of the conservative Islamist movement was behind the Kabul blast.

"URGENT CHANGES REQUIRED"

The two raids on Thursday are part of rising violence in the past two years, the bloodiest period since U.S.-led troops overthrew the Taliban's al Qaeda-backed government in 2001.

The increase in violence comes despite the presence of some 50,000 NATO-led troops in Afghanistan country.

Failure to defeat the Taliban insurgency in Afghanistan would deal a strategic defeat to the U.S. fight against Islamic extremism that would destabilise neighbouring Pakistan and threaten the future of NATO, two studies warned.

"Urgent changes are required now to prevent Afghanistan from becoming a failing or failed state," said a report by the Atlantic Council, a Washington think tank.

"If Afghanistan fails, the possible strategic consequences will worsen regional instability, do great harm to the fight against Jihadist and religious extremism, and put in grave jeopardy NATO's future as a credible, cohesive and relevant military alliance," it said.

Separately, the Afghanistan Study Group warned that "the mission to stabilise Afghanistan is faltering" amid renewed violence, rising opium production and falling Afghan confidence in their government and its international partners.

"The prospect of again losing significant parts of Afghanistan to the forces of Islamic extremists has moved from the improbable to the possible," the group said in a report produced by non-governmental experts and published by the Washington-based Center for the Study of the Presidency. (Writing by Sayed Salahuddin, editing by Sanjeev Miglani)

AlertNet news is provided by