INDIANAPOLIS -- A standoff involving a highly-trained Iraq War veteran near the Indiana University Purdue University-Indianapolis campus entered its seventh hour Tuesday with no end in sight.

Indianapolis police were called to the Lockefield Gardens apartments, at Indiana Avenue and Blackford Street, at about 4:30 a.m. after someone reported glass breaking in a disturbance inside one of the apartments, 6News' Julie Pursley reported.

When officers arrived, they found that there were two men inside an apartment who were involved in the dispute. One of the men escaped, but told police not to go inside, because he said the other man was heavily armed.

"Apparently, he was inside with who we believe to be a friend of his who was trying to negotiate that weapon being released at that time," said Sgt. Paul Thompson. "The officers stood their ground just outside the apartment and communicated with the individuals inside."

Police declined to release the man's identity, but said he is 26 years old and had been in the National Guard for eight years.

The man has had ranger training and served three tours in Iraq. He is now a student at IUPUI, with aspirations of going on to nursing school, police said.

About a dozen military personnel who know the man gathered outside the apartment Tuesday morning as police tried to get him to surrender, Pursley reported.

Police think the man is armed with a military-style rife and several rounds of ammunition, along with other guns, body armor, a gas mask and a vest.

Lt. Jeff Duhamell said the man has had several personal problems after arriving home from Iraq eight months ago, including a pending divorce and being the victim of a carjacking on Sept. 6.

The man's issues apparently hit a boiling point during a night of heavy drinking. Investigators said they are in no hurry to get the man out of the home and that they are concerned about the man's mental well-being, believing that he may be suffering from Post-Traumatic Stress Disorder.

"Everyone we have talked to, the people who've worked with him in the National Guard, says he's a very good guy," Duhamell said. "He's had trouble adjusting when he gets back."

Police also think the man suffered a cut on his hand in the initial altercation in the apartment. They are communicating with him through a phone that was thrown into the apartment.

Some people were evacuated from other apartment units in the area, and streets in the area were blocked off. The school sent out an alert to students to avoid the area.

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