For the second time in two months, Apple is putting one of the companies it hires to build the iPhone on notice for violating labor laws. Reuters, Bloomberg and others are reporting that Apple has put Taiwanese manufacturing giant Wistron on “probation” — meaning it won’t receive any new business from Apple until it sorts things out — after the supplier was found exploiting workers at a plant in India.

The reason we’re hearing about this at all is rather incredible: on December 12th, some 2,000 workers decided to protest unpaid wages by rioting at one of Wistron’s offices, smashing up the lobby and overturning vehicles.

Karnataka: #Violence at iPhone production plant run by Taiwan-based #Wistron Corp at Narasapura (in Kolar district) near #Bengaluru.

Employees allege they have not been paid properly. pic.twitter.com/GKbeFeyRKc

— TOI Bengaluru (@TOIBengaluru) December 12, 2020

It now turns out that the workers’ complaints were legitimate: Wistron is admitting as much, and the local government found serious labor violations in its preliminary investigation, according to the South China Morning Post and Reuters. They say Wistron was indeed underpaying wages and forcing some people to work overtime. And that’s just Wistron itself. The SCMP reports police are also investigating middlemen who are targeting Apple’s contract workers:

There have also been allegations of middlemen exploiting the contract workers and skimming their wages, with police looking into the role of six contractors who acted as go-betweens for Wistron. They reportedly lured workers by promising them an additional allowance if they forewent breaks.

The investigation also reportedly reveals that 8,500 of the Wistron factory’s 10,500 workers were contractors rather than full-time employees, and that the plant may have only been permitted for 5,000 workers to begin with. (Wistron started assembling iPhones in India back in 2017.)

Wistron issued an apology, saying that it’s “enhancing its processes and restructuring our teams to ensure these issues cannot happen again,” adding that it’s already established “a 24-hour grievance hotline” and “an employee assistant program.” The company says it also sacked its VP of business in India.

Apple didn’t immediately reply to our request for comment.

The question now is whether Apple will do anything meaningful to keep its suppliers from exploiting workers now that they’re making headlines yet again. The company has a notable history of being associated with labor violations, and a recent report suggested that Apple turns a blind eye to them even when it knows there’s a problem. Did Apple know about this?