( CNN ) -- Government shelling of the seaside town of Misrata resumed Thursday afternoon , with heavy artillery and mortars targeting residential areas , killing 10 people , a member of the medical committee of the Misrata Council told CNN . Also Thursday , rebels retook the border area of Dehaiba/Wazin after forces loyal to leader Moammar Gadhafi had taken it earlier in the day , a witness said . The witness , Yousef Gaigi , said about 100 rebel vehicles equipped with assault rifles and antiaircraft weapons drove from the Libyan city Zintan to the border area , where they clashed with pro-government forces . `` The fight resulted in many casualties , '' he said , without citing a number . Gaigi said the pro-Gadhafi forces then fled to the Tunisian side of the border and handed their weapons to the Tunisian army . The Tunisian Defense Ministry said the soldiers were taken farther north to the border at Ras Ajdir and sent back to Libya . Asked whether the Tunisians had returned the Libyans ' weapons , a ministry official said , `` It 's possible . '' Earlier Thursday , the Tunisian Foreign Ministry had expressed `` deep concern '' over the military escalation near the crossing its border with Libyan and demanded that the Libyan government `` put an end to these violations , '' according to the state-run Tunis Afrique Presse ( TAP ) . The incidents occurred a day after the carnage in Libya continued to mount : on Wednesday , pro-government forces launched the heaviest shelling yet on the port of Misrata , much of which appeared to be a wasteland , rebels said . Also Wednesday , a NATO airstrike on Misrata killed 11 rebel fighters and wounded two others , witnesses told a reporter , who saw the bodies . From the time NATO began its operation on March 31 until Tuesday , the organization had conducted 3,981 sorties , of which 1,658 were strike sorties , according to an update issued Wednesday . NATO is leading an international military operation in Libya that includes airstrikes targeting Gadhafi 's military resources . It is operating under a U.N. Security Council resolution authorizing any means necessary -- with the exception of foreign occupation -- to protect civilians . Misrata , the third-largest city in the North African country , has been hemmed in on three sides by Gadhafi 's forces . Though rebels said they had gained control of the city 's center and had pushed government forces outside the city , they said Gadhafi 's forces were continuing to attack Misrata with heavy weaponry . The port has served as a crucial route of escape and as a lifeline to humanitarian aid . CNN 's Frederik Pleitgen and Saad Abedine contributed to this report .
Ten are dead , a medical committee members says . Rebels retook a border area from pro-Gadhafi forces , who had seized it earlier in the day . The rebels have been fighting for control of Tripoli since last week and they say that their fighters will not give up until Gaddafi is gone.