Classes were disrupted after outsourced workers at the University of the Free State (UFS) embarked on an unprotected strike on Thursday.

UFS spokesperson Lacea Loader said the workers were demanding in-sourcing of all jobs at the university.

Loader said some students and student organisations had also participated in the strike.

Students and workers from the workers and students forum (WSF) handed over a memorandum to the institution's management during the Shimla Park commemoration prayer service last week Friday.

Management requested to "initiate a formal process of engagement and consultation on the proposed outsourcing".

"The WSF did not accede to this request and decided to embark on today’s [Thursday] unprotected strike action.

"Students participating in the unprotected strike action have been requested to uphold the right to education of their fellow students and not to participate in the disruption of classes‚" Loader said.

Loader said protection services were monitoring the situation on campus closely.

"The executive management remains committed to engage continuously with all its constituencies‚ including the WSF‚ in an open‚ transparent‚ and honest manner."