PORTLAND, Ore. – TriMet may suspend service in downtown Portland beginning Friday afternoon due to safety concerns surrounding the upcoming protests and marches following the inauguration of Donald Trump.

Harry Saporta, TriMet Executive Director of Safety and Security, said TriMet services will be maintained throughout the day "up until that particular moment when we believe it's necessary to alter ... or suspend our service."

If TriMet decides to suspend transportation services, it will be for downtown Portland only, in particular around Pioneer Courthouse Square, Saporta said. All other services will remain intact.

Saporta said there is no specific timetable for when services could be suspended Friday. He said there are no plans for suspension of service Saturday at this time.

"Our riders should be prepared and plan extra time. Those who take TriMet into work or school in downtown Portland Friday morning, are encouraged to head home early," said TriMet spokeswoman Roberta Altstadt.

C-Tran said it plans to stop routes that serve downtown Portland at around 2:30 p.m.

Portland is bracing for at least nine anti-Trump demonstrations, rallies and marches between Thursday morning and Saturday afternoon.

After Trump was elected in November, a series of protests turned into violent riots in Portland. Demonstrators smashed windows and windshields, took over the freeways, spray painted city property and threw objects at police.