Two students have been indicted in connection with an armed robbery last fall at Lamar High School, according to court records.

Rayshun Dewayne Dallas, 19, and Desmond Gibran Gaines, 18, are facing charges of aggravated robbery with a deadly weapon. A Harris County grand jury indicted them last week.

Houston Independent School District police first learned about the robbery around 7:30 a.m. Oct. 12, according to the arrest affidavit. The victim told police that he had been robbed at gunpoint shortly after dismissal the previous day.

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He said a student pulled a gun on him and asked for his money in the a third-floor restroom. Another student stood watch at the door as the gunman "cocked" his weapon and said "give me your money," he said. The victim said they stole about $220 from his wallet.

HISD police watched security camera footage that showed Gaines, Dallas and a third student walk toward the third floor restroom that day. The third student appeared to be serving in a lookout role in video footage, but he later told police he didn't have anything to do with the robbery, according to the affidavit.

In the video, police saw Gaines and Dallas running from the restroom down a stairwell to the first floor. The victim was seen following them for a short time. The two suspects eventually ran out of the building.

Later, school administrators pulled Dallas and Gaines from class. Dallas admitted to being in the restroom at the time but told police that he didn't know what happened, the affidavit said. Gaines also said he went to the third-floor restroom but that "nothing happened," the affidavit said.

At the time, police searched Gaines and found a jar of 11 baggies of marijuana, the affidavit said. They also found a loaded handgun in his car in the student parking lot, the affidavit said.

Both men were taken into custody after they were identified in a photo array.

Their next court date is scheduled for 9 a.m. May 3 in the 208th Judicial District Court.

Julian Gill is a digital reporter in Houston. Read him on our breaking news site, Chron.com, and on our subscriber site, houstonchronicle.com. | julian.gill@chron.com | NEWS WHEN YOU NEED IT: Text CHRON to 77453 to receive breaking news alerts by text message | Sign up for breaking news alerts delivered to your email here.