BEIRUT – Syrian rebels circulated dramatic video Monday of what they claimed was the downing of a warplane and armed men later holding the captured pilot who ejected as the MiG fighter was engulfed in flames. Syria acknowledged that a pilot bailed out of a disabled plane but blamed the crash on a technical malfunction.

The authenticity of the images or the claims could not be independently verified. If the rebels did bring down their first aircraft, that could signal a significant jump in their firepower and give opposition forces their most high-profile military captive.

But wider questions remain even if the rebel reports are confirmed, including whether this could be just a one-time blow against expanding air offensives by the forces of Bashar Assad’s regime. Just days ago, protesters across Syria pleaded for the rebels’ main backers — including Turkey and Gulf states — to send anti-aircraft weapons for outgunned fighters.

Assad’s military has significantly stepped up aerial attacks in recent weeks. Strafing from warplanes and close-range missile strikes from helicopter gunships have pushed back rebels in key fronts such as Aleppo, the country’s largest city and the scene of fierce attacks to dislodge rebel positions.

As the sun was setting Monday, an Associated Press reporter saw two fighter jets over the village of Marea, 20 miles north of Aleppo.

Terrified residents collected on street corners and near the doors to their houses to watch and point as the jets dived low, dropping bombs that sent up clouds of smoke and firing machine guns that crackled over the village.

On one crowded market street, a handful of rebels with rifles ran toward the site of the bombings. “What are you going to do, bring down a jet with a rifle?” a man screamed.

After the jets left, young men on motorcycles rushed to the bombing site on the edge of the village to find two craters the size of cars in a dirt field next to a swimming pool. A man working at the privately owned pool said only three people were there at the time and that none was injured.

It is unclear why the area was targeted. Residents said there was no rebel base nearby.

“In the summer, it’s hot so the guys gather here to swim,” said Abdullah Najjar, 21, adding that some of them could have been rebels. “This is the only place we have in town to come for entertainment.”

Nationwide, the relentless bloodshed — including alleged massacres by pro-regime mobs and retaliation killings by rebels — has already claimed more than 20,000 lives, activists say, and will be further examined in a report expected Wednesday by the U.N. Human Rights Council’s independent commission probing abuses in Syria.

In another crack in Assad’s diplomatic corps, a Syrian diplomat who worked with the U.N. rights council in Geneva said he left his post to join the opposition.

A spokesman for the council, Rolando Gomez, identified the Syrian as Danny al-Baaj and described him as a junior member of his country’s U.N. mission. Syria is not a member of the 47-nation council, but al-Baaj worked with it as part of his duties.

The claim of bringing down the warplane and capturing the pilot, meanwhile, is likely to become a key propaganda tool to rally rebel fighters.

Activists released a video which they say showed a government Soviet-made MiG warplane catching fire after it was hit by ground fire over Deir el-Zour province, an area near the Iraqi border where the opposition has strongholds.

Hours later, another video shown on the pan-Arab network Al-Arabiya purported to show the captured pilot surrounded by armed rebels. “Introduce yourself,” says another speaker with his back to the camera.

The alleged captive identifies himself as Col. Rafik Mohammed Suleiman and says he was on a mission to attack a rebel-held area.

“What do you tell the officers of the Assad army?” the speaker asks the man. The man who identified himself as the pilot urges them to defect.

The speaker — whose face remained hidden — said the hostage will be treated according to tenets of Islam and the Geneva Convention. The reference could be an indirect reply to recent international outrage over videos posted on the Internet claiming to show summary executions and torture by rebels.