SAN JOSE (CBS SF) — Law enforcement officers from far and away are expected to attend a memorial for slain San Jose Police Officer Michael Johnson and plans for the service could be announced as soon as Thursday, a police union spokesman said Wednesday.

A steady flow of officers came into the 4th Street headquarters of the San Jose Police Officers’ Association today as the union fielded a slew of messages of sympathy by phone and social media, union spokesman Tom Saggau said.

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“The outpouring has been so overwhelming we can’t keep up,” Saggau said.

Johnson’s family is to decide on the details of his funeral services, which are likely to feature a viewing prior to the memorial and burial, by Thursday, Saggau said.

“We expect large contingencies from across the country” to be present at the services, Saggau said. “It’s a solidarity in law enforcement in times of tragedy that really shines.”

On Tuesday night, Johnson, 38, a 14-year veteran officer who had been working as a field trainer for new recruits, was among the officers answering an emergency call about a distraught, intoxicated man that a family member feared might have access to firearms, including a rifle, police said.

At 6:50 p.m., as Johnson and other officers converged on a condominium in the 2600 block of Senter Road, a man later identified as 57-year-old Scott Dunham opened fire on them with a high-powered rifle from his balcony, striking the officer as police returned fire on Dunham.

Police set up a perimeter, blocked traffic in the area and waited for hours until officers from the Mobile Emergency Response Group and Equipment Unit forced their way into Dunham’s residence and found him lying shot to death on the balcony at 3:20 a.m. this morning.

Department officials have said only that there were no other shots aside from the first exchange and that it was not clear if Dunham died from being struck during the exchange or from a self-inflicted gunshot.

Meanwhile, police today released a statement from Johnson’s family addressing their loss.

“Last night Officer Michael Johnson of the San Jose Police Department was shot and killed while trying to help the community he loved.  We are deeply saddened by his loss and cannot express in writing how deep a hole in our hearts we are left with by his passing.

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“We appreciate all of the thoughts and prayers we have received from the community, both near and far and take comfort in your sharing our pain and in your recognition that police officers lay it on the line day in and day out as they work to make the world a better place.

“This is the statement the family intends to make and greatly appreciate having the space we need to allow our family to grieve and heal in private.

“We love you Mike our husband, son, brother, uncle and hero. Rest in peace.”

California Gov. Jerry Brown, Attorney General Kamala Harris, Santa Clara County District Attorney Jeff Rosen and Saggau of the police union were among those to issue statements of sympathy today about Johnson’s death.

San Jose Mayor Sam Liccardo said in a statement, “This is San Jose’s darkest day.”

Brown today had flags at the Capitol in Sacramento flown at half-staff in tribute to Johnson and Santa Clara County Board of Supervisors president Dave Cortese ordered flags flown at half-mast at all county facilities until April.

Johnson was the 12th San Jose police officer to die while on duty since the department’s founding in 1849.

According to the county Office of the Clerk Recorder, Dunham had acquired a condominium, where he died, at 2664 Senter Road with his wife Altheira Joyce Dunham.

Scott Dunham had worked for a period as a construction laborer for Central Services at De Anza College in Cupertino until leaving the job in 2012, according to an employee in the office of college President Brian Murphy.

A fundraiser is scheduled to run from 11 a.m. to 2 p.m. April 2 at Britannia Arms, 5027 Almaden Expressway. All proceeds will go to the Johnson family.

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