Microsoft Corp. activist employees and supporters were arrested after returning to the company’s headquarters for a second day to demand that the software maker sever business ties with the Israeli military.

Protesters set up a “Liberated Zone” at Microsoft’s Redmond headquarters, escalating pressure on the company to end contracts with Israel.

Police arrested 18 people at Microsoft’s Redmond headquarters after protests against the company’s ties to Israel. Demonstrators accused Microsoft of enabling Israeli military surveillance, while the company announced a new review into its technology’s use.