The Yemeni air force dropped bombs on armed tribesmen who seized an area outside the capital Sanaa, Al Arabiya television reported on Friday.
The broadcaster did not offer further details. The report comes after a tribal group said it had taken over an area about 100 km (60 miles) from the capital from Republican Guard troops loyal to President Ali Abdullah Saleh.
Meanwhile Yemeni opposition tribal chief Sheikh Sadiq al-Ahmar said on Friday that there is a truce between his fighters and security forces in Sanaa, but he is ready for war if the embattled president chooses.
"There is a truce between us and (President) Ali Abdullah Saleh" for mediation to take place, said Ahmar, head of the powerful Hashid federation, at a funeral for 30 of his fighters killed in clashes with Saleh's security forces in the capital.
"If the Saleh regime wants a peaceful revolution, we are ready for that. If he chooses war, we will fight him," Ahmar said. Saleh, who has been in power for 33 years, has since January faced protests calling for his departure.
Fighting broke out between Ahmar loyalists and security forces on Monday, a day after Saleh refused to sign a Gulf Cooperation Council-sponsored accord that would have seen him cede power within 30 days in exchange for immunity from prosecution.
Instead, Saleh issued fresh demands, including that the opposition sign the deal in his presence, and warned of civil war.