New satellite images suggest North Korea tested a long-range rocket engine last month, a U.S. research institute said Monday.

While the exact engine type could not be identified, possibilities included the second stage of the Unha-3 Space Launch Vehicle or the second or third stage engine of a much larger rocket under development, the U.S.-Korea Institute at Johns Hopkins University posted on its 38 North website.

The day after her stunning election triumph, German Chancellor Angela Merkel was Monday set to start the process of haggling with potential partners over how to rule Europe's biggest economy.

After a campaign that banked on Merkel's image as a calm, sensible and reassuring eurozone crisis manager, she led her conservative Christian Democratic Union (CDU) close to its first absolute majority in half a century.

South Korea on Monday urged North Korea to review its decision to postpone a reunion for families separated by the Korean War, saying it had "deeply wounded" those chosen to participate.

Hundreds of divided family members from both Koreas were scheduled to meet at the North's Mount Kumgang resort from Wednesday in the first such reunion for three years.

Kenyan security forces were locked in a fierce, final battle with Somali Islamist gunmen inside an upmarket Nairobi shopping mall on Monday as huge explosions and a barrage of heavy gunfire echoed out of the complex.

Thick black smoke billowed for several hours from the Westgate mall as Kenyan officials said the more than two-day-long siege -- in which the gunmen have massacred at least 62 people and taken dozens more hostage -- was close to being resolved.

Typhoon Usagi killed at least 25 people after crashing ashore in southern China, throwing the region's transport systems into chaos and leaving tens of thousands of airline passengers stranded in Hong Kong on Monday.

Schools and businesses were shut as activity in the normally teeming financial hub slowed to a crawl after Usagi punched a long swathe of Chinese coast with torrential rain and winds of up to 165 kilometers (103 miles) per hour during the night.

U.S. Secretary of State John Kerry said Sunday that the deadly mall siege in Kenya had highlighted the gravity of the threat posed by Somali militants.

Kerry said he had spoken with Somalia's foreign minister and ambassador to Washington earlier in the day about the attack on a Nairobi shopping mall.

U.S. President Barack Obama used a memorial service for the victims of America's latest mass shooting on Sunday to make another impassioned appeal to reform gun ownership laws.

"No other advanced nation endures this kind of violence. None," he declared, at a ceremony in the Washington Navy Yard, where a contractor killed 12 people in a gun rampage on Monday.

Five Americans were among those wounded when Somali militants stormed a Nairobi shopping mall, according to a statement by the U.S. State Department on Sunday.

"A number of American citizens were present in Westgate Shopping Mall at the time of the attack. Five American citizens are among the injured, but we have no reports of any American deaths," State Department spokeswoman Marie Harf said in a statement.

Severe Typhoon Usagi left two dead as it made landfall in southern China Sunday, shutting down one of the world's busiest sea ports in nearby Hong Kong and throwing flight schedules into disarray.

Usagi packed winds of 165 kilometers (103 miles) per hour as it closed in on China's densely populated Pearl River Delta, forcing some residents in vulnerable areas to tape up windows and stock up on supplies.

European Union president Herman Van Rompuy on Sunday congratulated German Chancellor Angela Merkel on her election win and expressed confidence that Germany would remain committed to a "prosperous Europe."

"I am confident that Germany and its new government will continue its commitment and contribution to the construction of a peaceful and prosperous Europe at the service of all its citizens," he said in a statement, adding: "I look forward to continuing the close cooperation with Angela Merkel."