Except for a lone Amtrak detective and periodic patrols from the local police department, there was little law enforcement at the spacious $53.1 million station, which is used by hundreds of travelers each day.

Soon, however, uniformed officers -- and even an occasional police dog -- should be a normal part of the bustling atmosphere.

Rensselaer County Sheriff Jack Mahar's deputies recently began patrolling the station and hope to ultimately open an office there to boost overall security at the busy transportation hub.

"Whether it's a purse-snatching or a terrorist activity, our goal is to cover the gamut," Mahar said. "We want people to know there's a police presence there if they need it. That comfort feeling is important in today's transportation business."

The sheriff's move comes at a time of heightened concern about rail security, both locally and internationally. Explosions on commuter trains in Madrid on March 11 killed almost 200 people, and an unexploded bomb was found less than two weeks later beneath a railway in France.

Even before the attack in Spain, Rensselaer officials called on Amtrak to put its own officers on round-the-clock duty or compensate the city for responding to calls at the station.

But Amtrak officials said the railroad can only afford to assign one full-time detective to the station.

The Capital District Transportation Authority, which owns the station, contracts with a security company that keeps an eye on television monitors hooked up to cameras around the building, makes rounds and provides escorts to cars. The guards are not armed or authorized to make arrests.

The CDTA budgets $70,000 for private security services, said authority spokeswoman Margo Janack. "It's just an added layer of security to alert whoever needs to be alerted if something is out of place," she said.

Mahar said the train station, where more than 620,000 boardings and arrivals take place each year, was identified as an underserved spot in an assessment done by department staff shortly after he took office in January.

The sheriff declined to describe the scheduling or frequency of the patrols.

"We're there quite often," he said, "but not to the level I want to be, yet."

The effort's first obvious payoff came this week, when a deputy was on hand to arrest an Albany County drug suspect as he stepped off a train from New York City.

Albany County Sheriff James Campbell said officers with his department developed information that Eric R. Dones, a roommate and alleged drug-trade associate of a man they arrested at a Madison Avenue apartment on Tuesday, was on his way home on an Amtrak train.

Word reached the Rensselaer County authorities, and the arrest was made by Sgt. Mark St. Germain, Mahar said.

Rensselaer and Amtrak authorities say there's room for more policing at the station. Railroad spokesman Dan Stessel noted that much of the Amtrak detective's time is devoted to "general security," which includes protecting the property from trespassers and vandals, and making sure bags are not left unattended.

That leaves little room for dealing with routine crime or more serious potential problems at the station, such as drug trafficking, Stessel acknowledged.

"We would certainly cooperate if the sheriff's department wanted to pursue that kind of crime fighting," he said.

Travelers will welcome the increased police presence at the station, said Anthony Rudmann, area coordinator for the Empire State Passengers Association.

"Certainly in the current climate, the presence of uniformed officers would probably give passengers a greater sense of security," he said.

The Albany County Sheriff's Department has several years of experience policing transportation hubs.

At Albany International Airport, Campbell said more than 20 deputies provide security services under a mandate from the Federal Aviation Administration. They patrol the perimeter, take people carrying drugs and guns into custody and deal with unruly passengers, the sheriff said.

"We make quite a few arrests up there," Campbell said. In addition to drug and weapons charges, "people do become disorderly out there, coming off of planes. Some people are intoxicated," he said.

The sheriff's airport security costs are reimbursed entirely by the airport, Campbell said. His department also conducts periodic patrols and sweeps at Albany's downtown bus station, a major port for drug traffickers traveling from New York City.

Aside from those typical local criminal problems, however, it is a renewed wave of post-9/11 rail security qualms that has sparked the most concern about police protection at train stations here and elsewhere.

Mahar said he hopes to fund much of his expanded operation at the rail station with homeland security grants, and officials said negotiations are under way for the deputies to occupy office space at the station.

Deputies' daily duties will likely focus mainly on routine quality-of-life issues such as disorderly conduct, traffic violations and automobile break-ins, Mahar said. Discouraging any perception of the station as a soft target or staging area for major mayhem also will be part of the department's core mission, he said.

"Eternal vigilance is the name of the game," said Mahar.