Mogadishu, Somalia ? Somali pirates have released an oil tanker that they hijacked a month ago on its way from the United Arab Emirates to South Africa, a maritime official said Sunday.

The MT San Carlo is now on its way to South Africa, said Andrew Mwangura, head of the Kenyan chapter of the Seafarers Assistance Program. It was not immediately clear whether a ransom was paid for the release of the Malta-registered vessel and its crew of 24, Mwangura said.

On Nov. 5, two boats of pirates attacked a luxury cruise liner. The Seabourn Spirit sped away and no passengers were injured, but one of the 161-person crew was wounded by shrapnel in the raid, which occurred about 100 miles off Somalia’s coast.

The International Maritime Bureau, citing a sharp rise in piracy this year, has been warning ships to stay at least 150 miles away from Somalia’s coastline.