The station is equipped with security cameras that cover the entire area, but it wasn't known if any evidence had been captured.
Capt. Jesse Moore, commanding officer of the base on Kodiak, said he wasn't aware of any threats or anything else that might have indicated problems at the station.
In their jobs with the Coast Guard, Belisle and Hopkins were involved with the installation, maintenance, repair and management of electronic equipment. Work they did with 11 other people last summer installing communication antennas on the remote Alaska island of Shemya was featured in a Coast Guard blog.
A woman who answered the phone at the Belisle home Friday identified herself as a family friend said the family was not commenting. Attempts to reach Hopkins' family were not immediately successful.
The Coast Guard has sent crisis response teams to Kodiak.
"As an organization with roots in saving lives and a focus on protecting people, this tragic event has shocked us all," Rear Adm. Thomas Ostebo said in a statement. "My thoughts and prayers are with the victim's families, their loved ones, and the entire Kodiak community."
Moore was to meet Friday with base personnel to discuss the shootings, Petty Officer Charly Hengen said.
"There is a sense of deep sadness here, not only in the town but at the Coast Guard base," Hengen said. "A lot of us are not related to each other but we treat each other like a family."
Associated Press writer Mark Thiessen in Anchorage and researcher Barbara Sambriski in New York contributed to this report.
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