The president of northern Somalia's breakaway Puntland region apologised today to two German tourists who were freed following two months being held hostage by pirates.

The pair looked ill and dishevelled after they were released by their captors late yesterday. They repeatedly broke down in tears as they sat alongside Puntland President Adde Muse at a news conference in Bosasso.

"We are really sorry for what happened. We put a lot of effort towards their release and I wish to thank everyone who helped," President Muse told reporters.

"If any pirate is caught now he will be jailed for 20 years or executed," he vowed.

The pair were hijacked off Yemen in June while sailing to Thailand. The pirates ransacked their yacht and then took them to northern Somalia by speedboat.

They were freed after a ransom was paid to the gang. An accomplice of the pirates said the gunmen were paid $1 million.

The two were named by German news magazine Der Spiegel last month as Juergen K. and Sabine M. They told the magazine, which managed to contact them by telephone through an intermediary, that they were beaten and given very little to eat.

A German foreign ministry spokesman said later today the two were being cared for in the German embassy in Nairobi.

"They are showing the stresses and strains of captivity but are in good shape considering the circumstances," the spokesman said in a statement.

Juergen K., who was heavily bearded after the ordeal, was asked to address the press after Muse spoke. But he could not, and the president consoled him as he sobbed.

The release of the pair followed the freeing on Tuesday of two Italian aid workers held hostage in the south since May.

Piracy has long been rife off the coast of anarchic Somalia.

But it has increased sharply since the start of last year, when the country's weak interim government drove an Islamist movement out of the capital Mogadishu.