Two days after violence broke out at an iPhone manufacturing facility near Bengaluru over alleged irregularities in payment of salaries, technology company Apple Inc on Monday said it was investigating if its Taiwanese contractor Wistron flouted supplier guidelines, Reuters reported.

“Our teams are in close touch with the local authorities and we are offering our full support to their investigation,” the company said in a statement.

On December 12, workers at Wistron Infocomm Manufacturing India Pvt Limited’s plant in Narasapura area of Kolar district in Karnataka vandalised the facility over non-payment of promised wages, according to The Indian Express.

“The workers vandalised the factory over a dispute in payment of salaries,” Kolar Deputy Commissioner C Satyabhama told the newspaper. “The whole reception area was damaged. Phones made at the plant were taken away. A car was burnt and two cars of the company were damaged.”

Officials said after the coronavirus-induced lockdown was imposed in March, salaries of workers earning between Rs 15,000 and Rs 21,000 per month, were cut by Rs 7,000-Rs 9,000. “It seems the workers were unhappy over wages not being paid as promised,” Satyabhama said. “The issue was never brought to the notice of the labour department or district authorities. They have brazenly attacked the plant. The company also never reported any unrest.”

In his complaint to the police, Wistron’s Administrative Officer TD Prashanth said that the company estimated the damage to be around Rs 437 crore, reported The News Minute. The company alleged that four cars, two golf cars, the canteen area, television sets, laptops, printers, phones, production machines, construction site containers, water purifiers, an ATM machine, personal documents, cash and more items were destroyed during the incident. The police said the total loss can be evaluated only after an assessment by the insurance company.

Following the incident, operations were suspended at the plant, located about 60 kilometres from Bengaluru. Nearly 160 people have been arrested in connection with the violence, Superintendent of Police Karthik Reddy told The Indian Express. A case of arson, rioting, robbery and obstructing the police has been registered, he added.

Karnataka Deputy Chief Minister Ashwath Narayan has said that those who took law into their own hand will be dealt with very strongly, reported NDTV. “At the same time, whatever justice has to prevail to the employees will also be taken care of,” he said.

On Monday, Apple said that it was dispatching additional staff and auditors to the facility, Reuters reported. “Apple is dedicated to ensuring everyone in our supply chain is treated with dignity and respect,” an unidentified company official told NDTV. “We have teams on the ground and immediately launched a detailed investigation.”

Meanwhile, Wistron said it was “deeply shocked” by the violence, which it blamed on “unknown persons...with unclear intentions”, according to Reuters. “The company always abides by the law, and fully supports and is cooperating with relevant authorities and police investigations,” it said in a statement to the Taiwan Stock Exchange.

Wistron is one of Apple’s top global suppliers and makes iPhone 7 and the second generation iPhone SE devices in the country.