LUXOR, Egypt (AP) -- A mother and two daughters were allegedly killed by male relatives in southern Egypt who believed they'd had affairs, the latest apparent example of so-called "honor killings" in which women are slain for violating traditional morals in the conservative region, a security official said Friday.

Police believe the 10 men stormed the house of the women, strangling them and beating them with sharp tools, the official said, based on the alleged confession of one of the suspects. The men wrapped the women's bodies in blankets, weighted them with stones and throw them in the river Nile, the official added.

He said one of the men, arrested on Thursday, gave a detailed account of the killings and said they were intended to protect the family's honor.

One woman's body was seen floating on the surface of the Nile near the town of Esna close to the ancient city of Luxor, the official added. Police are searching for the two other bodies and nine remaining suspects.

The official spoke on condition of anonymity because he was not authorized to speak to reporters.

Egyptian papers frequently incidents in which fathers, brothers or even sons kill their female relatives on suspicions that they are having affairs outside marriage.

Such incidents of "honor killings" are especially common in the conservative south and in the countryside, where women's actions are considered to bring shame on the family.

The practice is against Egyptian law, and perpetrators are prosecuted if they are arrested. Courts are sometimes sympathetic to the accused and give lighter sentences.