The first talks between the United States and North Korea since the death of Kim Jong-Il entered their second day Friday, as Washington seeks to restart denuclearization negotiations.

Glyn Davies, coordinator for U.S. policy on North Korea, said he hoped to "build on the serious and substantive discussions" held in Beijing on Thursday with a delegation from Pyongyang led by veteran negotiator Kim Kye-Gwan.

Suicide bombers armed with guns and grenades attacked a Pakistani police station on Friday, killing four officers in the second attack in as many days in the northwestern city of Peshawar.

The three attackers first opened fire with Kalashnikovs, then used hand grenades to blow their way into the building before detonating their suicide vests, senior police official Yameen Khan told Agence France Presse.

U.N. atomic agency chief Yukiya Amano is expected to outline in a report Friday why its team investigating Iran's suspected nuclear weapons drive returned empty handed this week, diplomats said.

IAEA chief inspector Herman Nackaerts and his team returned from Tehran on Wednesday with no progress in their search for answers from Iran on its alleged bid to develop nuclear weapons, leading Washington to brand the trip a "failure."

Nigeria's military chief said Thursday the Islamist Boko Haram sect, blamed for attacks that have claimed hundreds of lives, has ties to al-Qaida, the first time a top security official has publicly drawn such links.

"We have been able to link the activities of the Boko Haram sect to the support and training the sect received from AQIM (Al-Qaida in the Islamic Maghreb)," Air Chief Marshal Oluseyi Petinrin said.

WikiLeaks suspect Bradley Manning declined to enter a plea as the U.S. Army private was formally charged on Thursday with turning over a cache of classified U.S. documents to WikiLeaks.

Manning, a 24-year-old former intelligence analyst, was charged with 22 counts, the most serious of which is "aiding the enemy," which could send him to prison for life.

German Chancellor Angela Merkel asked for "forgiveness" on Thursday from the families of 10 people, mostly foreigners, believed killed in a seven-year murder spree by a neo-Nazi gang.

Merkel, who led a memorial ceremony at Berlin's concert hall attended by about 1,200 people including some of the victims' relatives, described the killings as both a "disgrace" and an "attack" on Germany.

International powers called Thursday for urgent action on Somalia, warning that the world will "pay the price" for failing to help the country tackle political unrest, Islamist militants and pirates.

But as officials from 50 countries and organizations gathered in London to discuss how to end two decades of unrest, Somalia's al-Qaida-allied Shebab insurgents vowed to "wage war" against any international peace initiative.

President Barrack Obama was Thursday forced to apologize over the burning of Korans at a U.S. airbase in Afghanistan, where three days of protests have killed 14 people, including two American soldiers.

Violent anti-U.S. protests have seen furious Afghans attack French, Norwegian and U.S. bases, shouting "death to America" after the Taliban exhorted their countrymen to kill foreign troops to avenge the incident at a U.S.-run base.

Seven U.S. Marines were killed when two helicopters collided in Arizona during a training exercise, the military said Thursday.

The accident occurred on a military training range near the city of Yuma on Wednesday evening and the troops who died were from the 3rd Marine Aircraft Wing based at Miramar, in southern California.

The European Union is preparing regulations that will shut out Iran's banks from a major financial clearinghouse used by virtually every country in the world, a senior official said Thursday.

The official, who spoke on condition of anonymity because of European Union rules, said the regulations are currently being worked on, but should be adopted "rather quickly."