A forensic team investigating the Sambhal violence site on Tuesday recovered six empty cartridges which were made in Pakistan, police said.
Besides, the team also found one empty cartridge which had 'made in USA' written on it, they said.
Superintendent of Police Krishan Kumar Vishnoi told reporters that on the request of the SIT formed to probe the November 24 violence, the forensic team, along with a municipal team, investigated the spot on Tuesday.
"A shocking thing came to light in this investigation, as six empty cartridges made in Pakistani ordnance factory were recovered," the district police chief said.
Vishnoi said that 'Made in USA' is also written on another cartridge recovered from the site.
He said that this is a 'very serious' matter and it will be investigated properly.
The SP said that some CCTVs were broken during the violence, but their DVRs (digital video recorder) are being searched.
"The police team will conduct searches on Wednesday as well in the violence-hit area," he added.
There has been a tense situation in Sambhal since the first survey of Shahi Jama Masjid was conducted on November 19 on the court orders following a petition which claimed once a Harihar temple stood at the site.
Violence broke out on November 24 when the mosque was being surveyed again.
During this, four people died and others were injured in a clash between the protesters and the police.
Vishnoi said that a total of 29 policemen were injured in the incident.
