TUNIS — One Tunisian policeman was killed and several others wounded in a shootout with gunmen on the outskirts of the capital on Thursday morning, news reports said, as police forces increased security measures just days before national elections on Sunday.

The gunmen opened fire after security forces surrounded a house in the Tunis suburb of Oued Ellil, where they believed that a group of insurgents were preparing an attack to disrupt the elections, the spokesman for the Interior Ministry, Mohammed Ali Aroui, told a local radio station, Radio Mosaique. At least one member of the national guard was killed and the operation was still continuing, he said.

Security forces encircled the house, and the siege lasted all day and into the evening. A woman and three children were also inside, according to Radio Mosaique. The police had brought the mother of one of the suspects to the scene, and she used a megaphone to call on him to let the children go and surrender, the station reported.

Image Members of the Tunisian national guard outside a house in Oued Ellil, outside Tunis, where gunmen fired on security forces during a raid on Thursday. Credit... Fethi Belaid/Agence France-Presse — Getty Images

In a separate incident in the southern town of Kebili, two men believed to be insurgents were detained and weapons confiscated after a local security guard was killed. Five soldiers were also reported wounded in a mine blast near the western border.