The US suspended Microsoft, a major IT outsourcer, and ​software maker Adobe from a key green-card program on Thursday while opening probes into nine top universities, widening a crackdown it says targets fraud and protects American ‌jobs.

Since taking office, US President Donald Trump has pursued a broad effort to reduce the number of foreign-born people in the US and curtail their pathway to residence and citizenship. Thursday's twin actions mark the broadest strike yet against skilled-worker immigration programs — potentially cutting off a common path to permanent residency for foreign tech workers — while putting some of the country's top research universities on notice.

"There has been no company in the United States, unfortunately, that has ​abused the system more than Microsoft," US Vice President JD Vance said. He said the company laid off 6,000 American workers last year while benefiting from 6,300 H-1B temporary worker visas ​and nearly 3,000 green cards.

Microsoft is the largest filer of permanent labor certification process (PERM) applications, according to data from the US labor department. Under PERM, which most employment-based ​green cards require, employers must show a foreign hire will not hurt US workers' wages or jobs.

The company said in a statement that about 80% of the H-1B applications it filed in the last fiscal year were to extend or change the status of current employees, not to hire new workers. In July, the company said it would cut 4,800 jobs, or about 2.1% of its global workforce.

Secretary of Labor Keith Sonderling said the suspension also covers some of the largest IT outsourcing firms in the world: Cognizant, Infosys, Tata Consultancy Services, Wipro, HCLTech and Capgemini.

Vance also said that nine universities, including Harvard, Yale, Stanford and the Massachusetts Institute of Technology (MIT), merit an investigation for alleged J-1 visa fraud.

"While we see a lot of H-1B visa fraud, we also see a lot of J-1 visa fraud. And this is where some of America's most elite universities bring in foreigners again to undercut the wages of American residents. Now, there are nine universities in particular that we believe merit an investigation," Vance said at a press conference.

(With input from agencies)