LOS ANGELES — A protest at Pershing Square in downtown L.A. led to Los Angeles police warning of police activity and heavy traffic congestion Tuesday night.

The protest was organized following the leaked Supreme Court document that indicates the high court’s plan to overturn Roe v. Wade, the landmark legal decision that protects a woman’s constitutional right to abortion.

Initially, the Los Angeles Police Department provided an escort for those attending the rally as they walked from the United States Courthouse on W. First Street to Pershing Square, according to Chief Michel Moore.

Around 8:50 p.m., the LAPD sent out a tweet urging people to avoid the area due to “police activity” which was expected to cause traffic delays and congestion.

Chief Moore later said that some of those who were in attendance at the rally attempted to “take the intersection” and some in the crowd threw rocks and bottles at officers as police tried to clear the area.

One officer was apparently injured, Moore said, although the extent of their injuries was unclear.

The activity led to the Police Department declaring a “citywide tactical alert,” meaning officers were to be on high-alert and expected to be on standby throughout the evening.

Tuesday night’s protests were one of hundreds across the country, including dozens in the Greater Los Angeles area. Prior to Tuesday’s conflict with police, the protests were considered peaceful and orderly.