A routine traffic stop in North Long Beach on Wednesday led to an arrest and officers seizing about 6,000 fentanyl pills, authorities said.

Long Beach police officers pulled a man over near the 6600 block of Downey Avenue at about 5:30 p.m., Wednesday, for tinted windows and not signaling while making a turn, police spokeswoman Shaunna Dandoy said. The driver also was driving without a license, she said.

“Fentanyl is incredibly dangerous and even a small amount can be lethal. It can be mistaken for other drugs and it is hard to know how the pills are made,” police said in a tweet.

Officers detained the driver and searched his vehicle, finding and seizing about one pound of narcotics, which they later determined to be fentanyl, Dandoy said.

Police arrested 37-year-old Juan Rochasoto from Bellflower on suspicion of possession for sale of a controlled substance. He was released the following day on a $50,000 bond.