Gunmen abducted the father of Syrian deputy foreign minister Faisal Muqdad on Saturday, apparently in reprisal for the arrest of one of their relatives, according to a government source and a watchdog.
"Today armed men abducted Mr Muqdad's father from his home in the village of Ghossom," in the southern province of Daraa, the government source said on condition of anonymity.
"They beat him up in front of his family then took him to Daraa city," said the source, adding that he is 84 years old.
There has been no immediate claim of responsibility for the abduction, which was first reported by the Syrian Observatory for Human Rights.
Observatory chief Rami Abdel Rahman told AFP earlier that Muqdad's father, who was not named, was seized "in reprisal for the arrest by regime forces of relatives of one of the armed men."
Abdel Rahman said negotiations were underway to free him.
Daraa province is the cradle of the insurgency against the central government and the scene of deadly battles between government forces and armed rebels.
The government considers all armed men as rebels fighting to topple President Bashar al-Assad.
Muqdad is considered as one of the most powerful voices of the embattled Syrian regime.
The conflict, which erupted as a peaceful uprising, has claimed more than 94,000 lives since it started in March 2011, according to the Britain-based Observatory which relies on a broad network of activists, doctors and lawyers for its reports.