Members of a US union disrupted the keynote speech of Cisco CEO John Chambers at the network equipment giant’s annual user conference on Tuesday with a protest against company lay-offs.

Representatives of the Service Employees International Union Local 1877 caused a disturbance as Chambers took to the stage at San Francisco’s Moscone Convention Centre, but were quickly removed.

The union members were reportedly protesting the recent lay offs of 75 janitorial staff at Cisco’s San Jose facility. However, Cisco insists that these redundancies were made by a contractor, not the company itself.