Viewpoint Construction Software, one of Portland's largest tech companies, told employees to stay home Monday because of an unspecified "security issue" at the company's headquarters at the east end of the Hawthorne Bridge.

Viewpoint employees received a note Sunday evening from the company instructing them to work from home on Monday and to wait for word from management before coming into the office.

Update: On Monday evening the company told employees the Portland office will reopen Tuesday. It hasn't yet publicly explained, though, why it closed Monday.

Portland police said they received a report of a weekend break-in at a coffee shop on the first floor of Viewpoint's main building on Southeast Water Avenue, but had not received any reports about Viewpoint.

Viewpoint's office was locked Monday morning, and a sign on the door said "Viewpoint is Closed Today!" A person who came to the door declined to comment on why the office is closed.

Private equity firm Bain Capital owns Viewpoint, which employed 800 altogether in 2015, the most recent year for which it reported employment data. That number included 300 at its Portland headquarters.

-- Mike Rogoway; twitter: @rogoway; 503-294-7699