An ordnance factory worker is struggling for life after a friend played a practical joke on him. He filled compressed air into the worker's intestine through his rectum by a high-power compressor, police said Saturday.

The incident took place Thursday in Muradnagar area of Ghaziabad but was reported Friday night.

Police said Rajendra Singh alias Pintu (30) was a contractual worker at the state-owned ordnance factory in Murad Nagar.

While on a break from work Thursday afternoon, he and his co-workers were sitting near the factory's compressor house.

As a joke, a friend and co-worker - identified as Ankit - placed the air pipe of the compressor into Pintu's rectum and opened the valve through which the high-pressure air ballooned his intestine, police said.

Pintu complained of serious pain in his stomach, and some other co-workers rushed him to a hospital, where doctors provided him first aid and referred him to the Meerut Medical College and Hospital.

Doctors said his condition was critical, and his intestine may have ruptured.

"If intestine is found ruptured, it should be repaired immediately, otherwise the infection would spread in the entire body which would be difficult to stop at a later stage," said Rajiv Tyagi, a doctor at the Meerut hospital.

A criminal case for voluntarily causing hurt by dangerous weapons or means has been registered against the accused co-worker.