A 20-year-old Lansing resident was arraigned Wednesday on charges that he robbed two MSU students in East Lansing at gunpoint on Sept. 21 in separate attacks.

Scott Alfred Sylvester, facing two counts of armed robbery and two felony firearm charges, was arrested earlier this week by Lansing police after detectives working the cases received an anonymous tip.

They continue to seek a second suspect.

During his arraignment at 54-B District Court in East Lansing on Wednesday, Judge Richard Ball ordered Sylvester to be held without bail, East Lansing police Capt. Juli Liebler said.

Police believe that Sylvester and a partner are responsible for two gunpoint robberies that occurred within 2 miles and 20 minutes of each other at night on Sept. 21.

During the first attack, a gunman approached a student as she walked her dog on the 500 block of West Lake Lansing Road. The gunman demanded the victim's bag.

About 20 minutes later, a man accosted another female student outside a sorority house on the 300 block of North Harrison Avenue. The man showed a gun before fleeing with the victim's purse.

The victims, who identified Sylvester from a photo lineup, were not injured.

"We've heard that people are a little bit more at ease now that we've identified one of the two suspects," Liebler said.

Liebler said Sylvester hasn't assisted police in locating a second suspect, described as a black man in his early 20s with thick dreadlocks that were tied back.

The victim in the first robbery told police she was approached by one man, while a second man waited in a 1980s station wagon.

The Sept. 21 gunpoint robberies were the first in a string of five aggressive thefts that occurred late last month. There have been 22 aggressive robberies in East Lansing this year.

Those with information about Sylvester's acquaintances are asked to call East Lansing police at (517) 337-2599.