Sanaa: Gunmen shot dead the German ambassador`s bodyguard in Sanaa on Sunday as others kidnapped a Sierra Leonean working for the United Nations Children`s Fund (UNICEF), sources said.
Gunmen in a vehicle opened fire at the bodyguard as he was leaving a store in the southern Hada district, where foreign embassies are located, a security official and witnesses said.
An earlier report said the ambassador herself had been the target of a failed kidnap attempt.
However, a foreign ministry spokesman said that Ambassador Carola Mueller-Holtkemper "is currently outside the country".
But "apparently there was an attempt to kidnap her bodyguard and he was shot dead when he resisted".
In Berlin, a foreign ministry spokesperson said only that the government was "making intensive efforts to clear up the facts".
Medics in Sanaa said the corpse of the bodyguard was taken to the Saudi-German hospital in the capital.
Security forces sealed off the area after the shooting.
Elsewhere, in the north of city, gunmen kidnapped a Sierra Leonean citizen who works for UNICEF, diplomatic sources said.
They said the man was seized at gunpoint from a UN vehicle, adding that his Yemeni driver was not abducted.
Foreigners are frequently attacked or kidnapped in Yemen, home to al Qaeda in the Arabian Peninsula (AQAP) which is viewed by the United States as the network`s deadliest franchise.
President Abdrabuh Mansur Hadi today urged security forces to "boost alert levels to restore security and stability" in the face of "terrorist threats", the Saba state news agency reported.
On Wednesday, the pan-Arab Al-Hayat daily quoted Foreign Minister Abu Bakr al-Qirbi as saying that ransoms paid to AQAP kidnappers have helped strengthen the network.
"Unfortunately, the ransoms that were paid to release hostages seized by the network have provided it with the money needed to renew its activity," he said.
AQAP militants are still holding Saudi Arabia`s deputy consul in Aden, Abdullah al-Khalidi, whom they seized in March 2012.
In addition to a ransom, they are demanding the release of female al Qaeda-linked prisoners held in Saudi Arabia in return for his release.
The extremists are also holding Nour-Ahmad Nikbakht, identified by Tehran as an administrative staff member of the Iranian embassy in Yemen, abducted on July 21.