Two Leeward convenience stores were struck within 2-1/2 hours of each other Thursday night and early Friday morning — the latest in a streak of armed robberies during late-night and early-morning hours.

Police arrested an 18-year-old Aiea man at 1:40 a.m. Friday for allegedly robbing both the Ewa and Aiea 7-Eleven stores.

The Ewa holdup occurred at 10:45 p.m. on Fort Weaver and Renton roads and involved two female victims, ages 38 and 58.

Police said the man entered the store wielding a dangerous instrument and demanded money and cigarettes, then fled.

Then the same man, armed with a weapon, entered the 7-Eleven in the Westridge Shopping Center at 1:15 a.m. and demanded property, police said. He fled, and police found him nearby, where he was identified and arrested.

Police booked him on suspicion of two counts of first-degree robbery and kidnapping in each of the cases. No one was reported injured.

Meanwhile, CrimeStoppers and the Honolulu Police Department are asking the public’s help in locating a man wanted in the robbery of the American Savings Bank at 1209 Piikoi St., next to the Beretania Street Safeway, Thursday afternoon.

The suspect is described as between 40 and 50 years old, 5 feet 5 inches tall, 160-180 pounds, with black eyes, a black long-sleeve jacket, a black undershirt, black surf shorts, a black baseball cap and sunglasses.

The robber entered the bank at 1:25 p.m., approached a teller and handed over a note demanding money. He fled in a black Toyota Sienna taxicab.

Those with information are asked to call CrimeStoppers at 955-8300 or *CRIME on their cellphones. The public may also send anonymous web tips to honolulu crimestoppers.org.

Six banks were robbed in the first 12 days of December.

Police say they suspect the same two or three men committed the six robberies. In most of these cases, the suspects told or indicated to tellers they had weapons, but no weapon was ever seen.

The main branch of American Savings Bank was robbed Monday. The suspect handed the teller a demand note, then said, “This is a robbery,” and demanded cash.

A man in his 50s described as having a distinct waddle, with white hair and a white mustache, hit First Hawaiian Bank’s Kapiolani branch Dec. 2.

On Dec. 3 a man in his 40s, short in stature — roughly 5 feet to 5 feet 4 inches tall — robbed the Chinatown branch of Bank of Hawaii and the Wal-Mart branch of American Savings Bank.

But another man in his 40s, with a description similar to the Dec. 3 robbery suspect, also waddled into the Kaimuki branch of Bank of Hawaii on Dec. 9.

Finally, on Dec. 6 a man in his 50s, described as about 5 feet 3 inches tall and weighing about 198 pounds, robbed the Waikiki branch of First Hawaiian Bank.

There have been 23 bank robberies this year, compared with 13 in 2015.

Oahu bank robberies are up this year by 77 percent.

At 1:20 a.m. Tuesday two men robbed The Shack in Hawaii Kai.

A manager at The Shack said the men had a handgun and pointed it at the bartender and told her to open the restaurant’s safe.

They then told everyone to get on the ground and took cellphones from customers before fleeing the restaurant with about $1,000, he said.