By KCRA 3 News

SACRAMENTO, Calif. —The Capitola Annex construction site and and the historic Capitol building was deemed safe after a threat prompted an evacuation on Friday.

The California Highway Patrol said both the construction site and building were cleared after completing a sweep of the area.

The Secretary of the Senate said in a message to staffers obtained by KCRA 3 that the annex construction team reported a threat that was made on the construction site.

The California Highway Patrol said the threat was written on a wall at the site and was discovered at 9:45 a.m.

Work crews were asked to leave the site out of an abundance of caution, and Senate employees working in the historic Capitol building were also told to leave that site. The construction crews could later be seen gathered on the west steps of the Capitol.

Lawmakers are not currently in session.

Workers at the Legislative Office Building and the Swing Space were not impacted, the message said.

The message said there was “no reason to believe the threat is credible,” but it was being assessed by the California Highway Patrol. CHP said it was sweeping the building as a precaution.

Chief Doug Lyons of Protective Services for the California Highway Patrol said, "We are taking it serious. We're sweeping the building with our K-9s and our personnel. Because it's a construction site, it's got tools, debris and boxes, and you can imagine how many floors of stuff are out there, so it's going to take us some time."

Construction crews waiting for updates were informed around 12:30 p.m. that they should wrap up for the day and go home. Some workers shared off-camera that they are still being paid for the day.

CHP said the historical west side of the Capitol building appears to be safe because walls and structures separate it from the annex. However, authorities are keeping people away from the area as a precaution.

Visitors expressed their surprise at the sudden evacuation. One visitor said, "As soon as I got into the building to start the tour, I met some employees who said we need to evacuate. They didn't give me a reason why." When asked if they were simply told to leave, the visitor replied, "Yeah, just get out."

CHP said they are reviewing video footage that may help identify a suspect. The investigation raises questions about who has access to the area where the threat was discovered by construction crews this morning. Depending on what investigators uncover, it could lead them to answers.

Crews are in the process of building a new $1.2 billion office building for lawmakers and the governor at the Capitol Annex construction site.

The project has drawn scrutiny over transparency issues.

Project leaders have required thousands of people to sign nondisclosure agreements, limiting public access to information. Under these agreements, the project's cost increased from $543 million in 2018 to over $1 billion by 2022, comparable to the cost of some NFL stadiums.

For years, project leaders would not update taxpayers on the cost of the building until this year. Decisions about the project are made by a small group of people without input from the public.

The Capitol building will reopen to the public for normal business hours on Monday, Oct. 5, at 9 a.m. CHP said it will continue to investigating the initial threat.