(ABC NEWS) -- Guards were taken hostage by inmates Wednesday inside a Delaware prison, putting all the state's prisons on lockdown as police swarmed the facility.

An attorney for the union representing guards at the prison says at least four guards and one counselor have been taken hostage by inmates.

Bruce Rogers, counsel for the Correctional Officers Association of Delaware, told The Associated Press on Wednesday that the inmates had taken control of one building at the James T. Vaughn Correctional Center and injuries to both officers and inmates have been reported. He said the building under inmate control houses between 120-150 people.

Rogers says there's been very little communication between the inmates and people outside the building. He says no demands have been communicated to the union.

The state Department of Corrections has released few details about the situation at the prison in Smyrna. All prisons statewide are on lockdown, per DOC policy. Rogers said he'd been briefed on the situation by the union president, who was talking to officials at the scene.

The prison is Delaware's largest correctional facility for men, housing about 2,500 inmates.

Geoffrey Klopp, president of the Correctional Officers Association of Delaware, said the Department of Correction commissioner told him that prison guards had been taken hostage at the James T. Vaughn Correctional Center in Smyrna. In a brief statement, the department said that DOC Response Teams and Delaware State Police were on the scene responding to a hostage situation.

A DOC spokeswoman said only that an emergency situation was reported at the Smyrna prison late Wednesday morning. The facility was placed on lockdown, as were all prisons in the state per DOC policy. Spokeswoman Jayme Gravell provided few details but described the situation as an isolated incident, adding that there was no threat to the public.

Gravell said firefighters were called to the scene after reports of smoke and were being held on standby.

Video from above the prison shows uniformed officers gathered in two groups along fences near an entrance to the prison. Later, video showed several people surrounding a stretcher and running as they pushed it across the compound. It wasn't clear if a person was on the stretcher. People could be seen standing near a set of doors with an empty stretcher and wheelchair.

According to the department's website, the prison is Delaware's largest correctional facility for men, housing about 2,500 inmates. It houses minimum, medium, and maximum security inmates, and also houses Kent County detainees awaiting trial. It is also the site of the state's death row and where executions were carried out. The prison opened in 1971.

In 2004, an inmate raped a counselor and took her hostage for nearly seven hours at the Smyrna prison, according to an Associated Press report at the time. A department sharpshooter later shot and killed 45-year-old Scott Miller, according to the report, ending the standoff.