Israeli police have become increasingly convinced that 16-year-old Jerusalem resident Muhammad Abu Khdeir was murdered Wednesday morning as revenge for the killing of three kidnapped Israeli teens, officials said Wednesday evening.

According to the testimony of local residents, Abu Khdeir was seen being forced into a car by three Israelis in East Jerusalem late Tuesday. Police later confirmed a body was found in a forest in West Jerusalem.

DNA tests proved the body was that of the missing teenager, his family said.

An official familiar with the investigation told Israeli news site Walla that investigators were leaning toward revenge as the motive behind Abu Khdeir’s killing.

“The assessment now is that this was nationalistically motivated,” the source said.

Security camera footage from the scene of Abu Khdeir’s kidnapping strengthened investigators’ suspicions that Jewish extremists snatched the teen, Channel 2 reported.

Police are still looking into the possibility of a criminal motive for the attack, or even an honor killing, but sources told Channel 10 that the family has no criminal history.

Friends and relatives of Muhammad Abu Khdeir, the Palestinian teen found dead in the Jerusalem Forest, mourn in the family home in Shuafat, East Jerusalem, on July 2, 2014. (photo credit: Hadas Parush/Flash90)

Friends and relatives of Muhammad Abu Khdeir, the Palestinian teen found dead in the Jerusalem Forest, mourn in the family home in Shuafat, East Jerusalem, on July 2, 2014. (photo credit: Hadas Parush/Flash90)

The sources also said rumors claiming that Abu Khdeir was killed because he was gay, or because he’d had sexual encounters with local girls, are baseless.

The White House and US State Department on Wednesday condemned the killing, warning that acts of vengeance would worsen an explosive situation.

Prime Minister Benjamin Netanyahu ordered a swift probe into the killing Wednesday.

Police spokesman Micky Rosenfeld told The Times of Israel that officials were investigating the possibilities that Abu Khdeir was killed in a family honor killing, or that it was a nationalistically motivated slaying.

The killing set off violent riots in the East Jerusalem neighborhood of Shuafat, where protesters clashed with police and burned down a light rail stop.

Tensions have soared since June 12 when three Israeli teenagers were seized while hitchhiking in the West Bank. Their bodies were found on Monday afternoon near Hebron, with Israel blaming Hamas and vowing to hit it hard. Two Hamas members, Marwan Kawasme and Amer Abu Aysha, who disappeared on June 12, have been named by Israel as the prime suspects and are still at large.

AFP contributed to this report.