Apple has placed Wistron Corp, the Taiwanese contract manufacturer of its smartphones, on probation after detecting lapses in payments to employees at its facility near here.

The phone-maker said in a statement on Saturday that Wistron would not receive any business until corrective steps were taken.

The action came a week after hundreds of workers went on the rampage and vandalised the factory located at the Narsapura industrial area in Kolar district, some 75km from Bangalore on December 12.

They had accused the company of arbitrary deductions in salaries even after introducing 12-hour work shifts in place of three eight-hour shifts.

“Apple employees, along with independent auditors, will monitor their progress. Our main objective is to make sure all the workers are treated with dignity and respect, and fully compensated promptly,” said the company.

It admitted violations at the Wistron facility.

“While these investigations are ongoing, our preliminary findings indicate violations of our supplier code of conduct by failing to implement proper working hour management processes. This led to payment delays for some workers in October and November,” Apple said.

In a separate statement, Wistron said it has sacked vice-president Vincent Lee, who oversees its India operations, and admitted lapses in proper payment to its employees. It added that the entire team was being restructured to ensure such issues do not recur.

“Since the unfortunate events at our Narasapura facility we have been investigating and have found that some workers were not paid correctly, or on time. We deeply regret this and apologise to all of our workers,” the company stated admitting the lapses.

“This is a new facility and we recognise that we made mistakes as we expanded. Some of the processes we put in place to manage labour agencies and payments need to be strengthened and upgraded,” the company said.

The company has established a 24-hour grievance hotline in Kannada, Tamil, Telugu, English and Hindi for workers to voice their concerns anonymously.

“We are deeply committed to our business and employees in India. We are working diligently on corrective actions to ensure this does not happen again,” it said.

The action comes a day after the Karnataka government wrote to the union labour department citing some technical issues in recording attendance at Wistron’s Narsapura facility.

The report noted that increasing working hours from eight to 12 hours and wages getting deducted due to the malfunctioning of the attendance system had led to the unrest.

A government fact-finding team had reported that the Wistron facility had switched to 12-hour shifts from October 4 and manpower was increased from 5000 to 10,500 in a short period of time.

The vandalism had come as a major embarrassment for the state government, especially because chief minister BS Yediyurappa had received director-general of Taipei Economic and Culture Centre Ben Wang and discussed investment plans a day before the incident.

While Wistron had initially put the extent of damage at Rs437 crore, the company scaled it down to Rs41.25 crore in a letter to the local police.