An aircraft, described by bystanders as being the size of a car, reportedly crashed into Beijing's tallest building, CITIC Tower, on Friday.

The incident prompted a rapid police response, with roads around the 1,732 ft skyscraper closed and officers preventing passersby from filming the scene.

The 108-storey structure, also known as China Zun, dominates Beijing's central business district and serves as the headquarters for the state-owned conglomerate CITIC Group.

A heavy police presence was observed at the site, with several approach roads restricted to traffic.

Officers were seen preventing individuals from taking photographs and instructing others to delete any images they had captured, while simultaneously ushering people away from the building.

Initial reports indicate that two glass panels on a high floor sustained damage.

A courier whom Reuters spoke to near the building said he had rushed over to CITIC Tower around 6pm local time (1000 GMT) from a nearby location after hearing a loud crash as a aircraft about the size of a car hit the building.

"It was so loud – louder than fireworks," he said.

He said he had shot a video of the aircraft sticking out of the building, but later deleted it because he was scared of getting caught by police.

Another courier, whom Reuters spoke to, said he had come to the scene after seeing unverified social media images showing wreckage of a small aircraft on a road next to the building.

Social media posts of the building on Friday were quickly removed from Chinese social media. A search of the building's name on the Xiaohongshu app returned only posts dated Thursday.

Dozens of police cars and several fire trucks lined the roads around the building.

A police officer told Reuters journalists to depart from the scene. Asked why they had to leave, the police officer said: "We all know why!"

There has been no immediate official comment regarding the incident. Beijing's municipal government did not immediately respond to a faxed request for comment from Reuters outside of business hours.