At least 20 tourists were injured and 40 others were trapped by wasp attack Wednesday afternoon in a famous tourism site in central Sri Lanka, a local media report said.

The Daily Mirror newspaper reported on its website that 20 persons were injured in a wasp attack and admitted to the hospital at Sigiriya, a place about 160 km north east of the capital Colombo and famous for a 1500-year-old fortress built on the top of a huge rock.

The newspaper said two foreigners were among the injured and the rest were mostly school children.
About 40 persons were trapped at the top of the rock and the security forces were attempting to evacuate them, Xinhua reported.

Sigiriya -- means Lion's rock -- is an ancient rock fortress and palace ruin surrounded by the remains of an extensive network of gardens, reservoirs, and other structures.

The rock is a popular tourist destination within the cultural triangle, which includes five of the seven world heritage sites of Sri Lanka.