The police said reason behind the anxiety among people was the unusual shape of the balloon.
A balloon in the shape of fictional comic character Iron Man let loose in the skies sparked fears of an alien invasion among the residents of Dankaur town in Greater Noida, Uttar Pradesh, the police said.
The balloon filled with gas, that resembled a robot due to its Iron Man structure, was spotted over the town early Saturday morning, which later landed in a canal near Bhatta Parsaul village. A crowd gathered at the spot to see what some of them thought was "an alien", officials said.
"It was a balloon filled with air that had gone up in the sky and later came down and got stuck in the bushes along the canal. A part of the balloon was touching the flowing water in the canal which had led the balloon to shake a little. Unbeknown to the spectators, this made for an anxious watch," Dankaur police official Anil Kumar Pandey said.
He said a major reason behind the anxiety among people was the unusual shape of the balloon.
"It was shaped like the Iron Man (fictional superhero character) given its colour and design. This was an unusual sight so some people even thought it was an alien, or something like that, and were apprehensive," Mr Pandey added.
The official said the balloon, which must have come down as it ran out of gas, was fished out around noon from the canal.
There was nothing harmful in the object but it is yet to be known who let it loose it in the air, the official said.