D.C. Police Chief Charles H. Ramsey said yesterday that authorities believe they have captured some of the robbers who have been striking Washington area banks this year, but that additional suspects are being sought.

Charges have been filed against only one person so far, but Ramsey said five suspects are in custody. The others are jailed on unrelated charges while authorities analyze evidence seized Friday in three raids in the District and Maryland. One of the suspects collapsed just before a court hearing yesterday and was taken to a hospital for treatment.

"There's loose ends that need to be tied up," Ramsey said. "We have reason to believe that there may be more people we need to get a hold of -- as many as seven or eight people are part of this robbery crew."

Federal and local authorities raided two apartments and a rowhouse before dawn Friday, turning up assault weapons, body armor, dye-stained cash and other items that officials hope to link to the six robberies blamed on the gang.

Ramsey said analysts are conducting tests to determine whether the weapons recovered Friday can be tied to the robberies. Shots were fired during three robberies, but no one was hurt. Analysts are tracing seized money to see if whether came from the banks involved, Ramsey said.

All told, the robbers have stormed into four banks in the District and two in Prince George's County since January, wielding assault weapons as they stuffed containers full of cash. They escaped with more than $350,000, including $23,000 in the most recent robbery June 29 at a SunTrust branch in Northwest Washington; in that case, the money was rigged with red dye that stained it.

The weapons recovered with the suspects so far, as well as money bearing dye stains, provide a "strong case," Ramsey said, adding, "We're very optimistic that we have some of the people involved."

Aaron B. Perkins, 27, of Oxon Hill is the only person charged in the holdups. He was ordered held without bond at a hearing Friday in U.S. District Court in Maryland on charges of conspiracy to commit bank robbery and being an accessory after the fact.

Perkins was arrested early Friday in Silver Spring. Authorities later raided his apartment and found two assault rifles, a handgun and body armor, police said.

A second raid was conducted at the apartment of a girlfriend of Miquel Morrow, whom police described as a robbery suspect. Morrow, 26, of Northwest Washington, was arrested and jailed on warrants charging him with two shootings this spring in Northwest.

Morrow was scheduled to appear yesterday in D.C. Superior Court but collapsed before he was brought into the courtroom, officials said. They provided no details about his condition.

The third raid turned up the largest cache, authorities said. More than a dozen guns, body armor and dye-stained cash were taken from a rowhouse in the 3100 block of Sherman Avenue NW, they said. Guidel Olivares, 45, was charged with a weapons offense.

Olivares was ordered jailed without bond Friday after a hearing in D.C. Superior Court. Authorities said he also is a suspect in the bank robberies.

Police officials said that the other two suspects already had been in custody for other offenses. They were identified as Lionel Stoddard, 23, and Noureddine Chtaini, 29, both of Northwest Washington.

Stoddard has been jailed since his arrest June 28 on charges stemming from a shooting that he allegedly carried out along with Morrow. Chtaini was arrested July 11 in Alexandria by the Capital Area Regional Fugitive Task Force, led by the U.S. Marshals Service, after allegedly attempting to carjack two cars.