AP FACT CHECK: Syria's Assad on Aleppo, siege and airstrikes

During an interview with The Associated Press, Syrian President Bashar Assad made several denials, insisting that the city of Aleppo is not under siege and that Syrian and Russian aircraft did not carry out a strike on an aid convoy. He also said a U.S.-led coalition airstrike that killed more than 60 Syrian troops in the eastern Deir el-Zour province was "not an accident."

Here's a closer look at his statements and the facts surrounding them.

THE AID CONVOY

ASSAD: The Syrian president denied Syria or Russia carried out Monday's attack on the aid convoy that killed 20 people, many of them aid workers. He suggested rebels were to blame, saying the area was under their control. He claimed that at the time of the attack, "terrorists" were striking government forces with missiles, and that his forces didn't respond in a show of restraint.

He questioned whether witnesses of the attack were credible and said videos of the incident showed only "a burnt car, destroyed trucks, nothing else."

FACTS: The convoy, organized by multiple aid agencies and led by the Syrian Arab Red Crescent, was the latest in a regular mission delivering supplies from U.N. agencies to rural rebel-held areas in Aleppo province. For the September trip, it had obtained all necessary clearances from the government, rebels as well as the Americans and Russians, who operated aircraft in Syrian skies.

The convoy was at one its warehouses in the town of Uram al-Kubra, west of Aleppo city. The attack began after nightfall as staffers loaded trucks.

Witnesses described no fewer than 20 missiles striking the warehouse and trucks over a two-hour period. They said they heard aircraft and that among the blasts were barrel bombs, which are dropped from government helicopters. The rebels have no aircraft.

Video taken by a local activist shows part of the attack, with a missile streaking down from the night sky, causing a huge explosion and ball of fire. The sound of aircraft overhead is clearly heard. Other footage shows buildings in flame and burned bodies, as well as piles of aid supplies.

The witnesses at the scene included rescue workers and paramedics, as well as the brother of the head of the Red Crescent, who was killed in the attack.

The top U.S. military officer, Marine Gen. Joseph Dunford, chairman of the Joint Chiefs of Staff, told a Senate committee Thursday he believes Russia bombed the convoy and said Syrian and Russian aircraft were in the area at the time.

ASSAD: He said "even the United Nations said that there were no airstrikes against that convoy."

FACTS: The U.N. has not said it was not an airstrike. "We are not saying what it was. We are saying that we are not in a position to determine the exact nature of the attack," Jens Laerke, deputy spokesman for the U.N. humanitarian agency, said Thursday,

ASSAD: He said that in the years of conflict, no international organization or aid convoy has come under attack.

FACTS: Syria is one of the world's most dangerous zones for aid workers. At least 54 Red Crescent volunteers have been killed in Syria. Aid groups and international convoys have reported coming under fire, both from government forces and rebels.

DEIR EL-ZOUR STRIKE

ASSAD: He said he didn't accept the U.S explanation that it was a mistake when U.S.-led coalition aircraft this weekend attacked Syrian troops in the eastern province of Deir el-Zour, killing over 60 soldiers. He said the strikes hit a "huge" area for more than an hour, with no militants "adjacent to the Syrian troops there."

FACTS: Few independently confirmed details of Saturday's strike have emerged. The U.S. military said it may have unintentionally struck Syrian troops while carrying out a raid against the Islamic State group. Britain, Denmark and Australia have since acknowledged that their planes took part in the airstrike. The State Department called Assad's claim the strike was intentional "ridiculous."

The Syrian government controls about 40 percent of Deir el-Zour city while the Islamic State group controls the rest of the city and the surrounding province. The strikes took place near the government-held airport, a frontline area where Islamic State group fighters were launching attacks.

ALEPPO SIEGE

ASSAD: He denied that his government obstructed aid delivery to the rebel-held eastern part of the city. He said many aid convoys had been allowed to other areas in Syria over the years, "so why does the Syrian government prevent a convoy from coming to Aleppo?" He also said there is no siege on Aleppo, adding that if there were, "people would have been dead by now."

FACTS: The U.N. blamed the Syrian government for the failure to deliver aid to Aleppo during the cease-fire last week. Several days into the truce, the UN.'s envoy for Syria, Staffan de Mistura, said Damascus had not provided needed "facilitation letters."

U.N. officials have often complained in the past of blocked aid deliveries.

Earlier this year, aid convoys were prevented from reaching 15 of the 18 besieged areas around Syria. As a result only around 750,000 of the nearly 5 million Syrians living in hard to reach or besieged regions received assistance, according to the U.N.

Aleppo has been a battlefield since July 2012. During that time, the opposition eastern neighborhoods that are home to around 300,000 people had open supply routes to rebel territory in the surrounding countryside.

The complete siege is more recent. This year, government forces backed by Russian airstrikes advanced and finally, on July 17, they captured the Castello road, the last main artery into eastern Aleppo, cutting it off completely for the first time.

That seal lasted around 40 days, with no supplies entering. In early August, rebels from outside Aleppo city broke the siege, recapturing a corridor. Some food and medicine made it into the neighborhoods, until government forces retook the roads, re-imposing the siege in early September. Since then, international aid groups say no humanitarian supplies have reached those areas.

HOSPITAL ATTACKS

ASSAD: He denied attacking hospitals, saying, "How can I attack hospitals while I am sending vaccines, for example?"

FACTS: The U.N. rights agency, UNICEF and other U.N. agencies have repeated condemned airstrikes on hospitals and medical facilities. The aid group Doctors Without Borders has several times reported that hospitals it works with in opposition areas have been hit. The U.S.-based Physicians for Human Rights recorded 382 attacks on medical facilities and hospitals throughout Syria since the start of the conflict in 2011. Of those, 293 were carried out by government forces and 16 were by Russian warplanes, it said.