Alert troops of Border Security Force noticed suspicious movement on the border at midnight, a BSF spokesman said.
The troops saw two persons trying to throw something over the border fence from Pakistan side, he said, adding that they immediately alerted the adjoining nakas and fired on the suspicious persons.
The alleged intruders then fled towards Pakistan, taking advantage of thick growth of sarkanda and dense vegetation, he said.
After testing, the recovered substance was found to be heroin, he said.
