Hundreds of people have fled a major shopping centre in Thailand’s capital Bangkok after what sounded like gunshots were heard inside.

It was not immediately clear if shots had been fired, though police said there were injuries and some frightened shoppers were still sheltering inside the Siam Paragon shopping centre.

The incident prompted authorities to shut access to the nearby Siam elevated train stop, preventing commuters from exiting the transit station, as the evening rush hour began and intense rain fell in the city, according to an Associated Press journalist at the scene.

Emergency services could be seen entering the shopping centre as sirens wailed outside.

Police spokesman Archayon Kraithong said officers in the area had been ordered to secure the scene, and that he would provide details as soon as possible.

He did not provide details on casualties, but police said on their official Facebook page that there were injuries.

Witnesses said crowds of people left the building, one of several shopping centres in the area popular with tourists and Thais alike.

Chinese tourist Liu Shiying told the AP that she saw people running and saying someone had opened fire. She said she heard gunshots and an alarm ringing out and that the lights in the shopping centre went out.

“We’re temporarily hiding. Who dares to go out?” she said while taking cover. She was later able to leave.

Multiple videos uploaded to social media showed people running out of the building. The public broadcaster Thai PBS said several gunshot-like sounds were heard, but had no other details.

Shopping centre officials could not immediately be reached for comment.

The incident happened days before Thais were planning to mark the one-year anniversary on October 6 of a gun and knife attack at a rural daycare centre that killed 36 people, most of them infants.

Gun violence is not uncommon in Thailand, though mass shootings are rare.