The security mantra goes: If you see something, say something. But some people also contact the authorities when they smell something.

It happened Monday in Howard County and led to the arrests of five men suspected of manufacturing methamphetamine at a hotel in Elkridge, county police said.

About 10:40 p.m., police said, they received an anonymous call reporting a strange odor in a Holiday Inn Express. Police said officers went to the hotel, on Marshalee Drive, and “detected a strong, unusual odor near the door” of a room on the fourth floor.

According to a statement, after officers knocked on the door, they were let into the room, where they spotted chemicals.

Three men were immediately taken into custody, police said, and a fourth was arrested after he showed up at the room. Police said that a fifth man had been staying there and that he was arrested in the hotel parking lot.

According to the statement, investigators think the men were making methamphetamine for their own use.Police said the men were traveling through the area for work and were making the drug because they could not find any nearby.

Two men were from Oklahoma, and the others were from North Carolina, Michigan and Pennsylvania, police said. They were charged with drug manufacturing.

Authorities say the process of making methamphetamine causes strong odors similar to those of ammonia and ether. The smells have been compared to the stench of cat urine and rotten eggs.