(CNN) -- A Planned Parenthood clinic in Wisconsin remained closed Monday after a homemade bomb was placed outside the building, the state organization said.
The explosive device was found around 7:40 p.m. Sunday at the Appleton North Health Center and had caused a small fire by the time Grand Chute fire officials arrived, Teri Huyck, president and CEO of Planned Parenthood of Wisconsin, said in a statement.
No patients or staff members were at the health care center at the time, Huyck said, and no injuries were reported. The clinic remained closed Monday as a precaution, but the organization says it will reopen Tuesday.
"Rest assured, our doors will remain open for the thousands of women who rely on Planned Parenthood of Wisconsin each year for high quality health care," the statement said.
Police in Grand Chute are investigating the incident. No information about a suspect or a motive has been released.
A statement from Planned Parenthood said the Appleton North Health Center provides abortion care at three of its 27 clinics in the state. It did not say which clinics provide those services.