Pakistani Taliban militants say they are holding a Swiss couple kidnapped earlier this month as they traveled through the country's restive southwestern province of Baluchistan.

The deputy head of the Tehrik-i-Taliban Pakistan , Wali-ur Rehman, told media outlets Friday that the couple was in good condition and that his group would release them in exchange for a Pakistani scientist jailed in the United States.

Aafia Siddiqui is a female neuroscience specialist given an 86 year sentence after an American court found her guilty last year of the attempted murder of U.S. security officials in Afghanistan. Her sentencing caused a public uproar in Pakistan, with mass protests across the country where anti-American attitudes are rampant. The Pakistani government also deplored the fact that her trial was in the United States.

Rehman said if Washington does not release Siddiqui, a Taliban court would decide the Swiss couple's fate. He did not give any deadlines.

Authorities believe militants are holding the couple in the South Waziristan tribal region, a notorious haven for Taliban militants along the Afghan border.

On Friday, the United Nations Security Council put the TTP on its anti-terrorism sanctions list. Diplomats have been seeking to put more pressure on the group, which allegedly has ties to al-Qaida and designs to expand its attacks outside Pakistan.

Meanwhile, police in Baluchistan's capital Quetta say unknown gunmen killed seven people at a bus terminal Friday. The victims were waiting for a bus heading to neighboring Iran, and included some people of non-Baluch origin.

The Swiss tourists — a man and a woman — had been traveling through Baluchistan by car earlier this month. Pakistani officials said they registered at a checkpoint before entering the province's Lorali district, where witnesses said they were abducted at gunpoint.

Kidnappings of foreigners are common in Baluchistan, the scene of a separatist insurgency and criminal gangs.