TOKYO (AP) — Japanese police on Tuesday surrounded a post office where a man with a gun was holed up, and said the case may be linked to an earlier apparent shooting at a nearby hospital in which two people were wounded.

Saitama Prefectural Police said two men — a doctor in his 40s and a patient in his 60s — were wounded after blasts resembling gunfire were heard at a general hospital in the city of Toda, just north of Tokyo. Police did not give details of how exactly the two people were injured.

The two victims are both conscious and their wounds are not life-threatening, police said. Kyodo News agency said the two were believed to be inside a consultation room on the first floor when they were attacked.

Saitama police are also investigating another case involving a man carrying a handgun holed up inside a post office in the city of Warabi, just north of Toda. They said the two cases are being investigated together because of a possibility that they involve a same suspect.

Police said the alleged gunman could be seen through a glass window at cash machines, but there was no obvious sign that he had taken hostages. A number of post office staff safely escaped from the building, while two of them may still be inside but they are believed to be safe and may not have been seen by the gunman, police said.

In a third suspicious case, police are also investigating a fire that broke out at an apartment building near the hospital in Toda just around the time of the shooting.

Japan has strict gun control laws, but in recent years, there has been a growing concern about handmade weapons, such as the one allegedly used in the July 2022 assassination of former Prime Minister Shinzo Abe.