The International Committee of the Red Cross said Tuesday that it had suspended its operations in Yemen's war-ravaged second city Aden after gunmen stormed its office.

"Gunmen stormed our sub-delegation in Aden yesterday (Monday) and held our staff at gunpoint," spokeswoman Rima Kamal told AFP. "We have as a result temporarily suspended our operations in Aden."

She said that the ICRC had evacuated 14 of its employees from Aden to other provinces.

Another ICRC spokesman, Adnan Hizam, said that the unknown assailants "robbed the office" but that personnel "were unharmed and are in good health".

"Our personnel in Aden had previously come under several attacks," he said without elaborating. "We have suspended our activity in Aden due to the security situation but will soon return to work."

Aden was the scene of months of intense fighting between troops loyal to exiled President Abedrabbo Mansour Hadi and rebels who overran the city in March.

Desperately needed aid has begun to flow into Aden during the past few weeks after loyalists recaptured the city in mid-July, but security remains fragile.

Al-Qaeda fighters -- believed to have entered Aden several weeks earlier -- were accused Saturday of blowing up a building used by the secret police.

They also set up checkpoints in one district and seized five buildings including an intelligence services facility, a presidential residence and a military hospital, security officials said.

Last week, Aden governor Nayef al-Bakri survived a rocket attack that killed four people and wounded 20 others. The assailants were not identified.