Speaking at a press conference on Sunday, Davoud Mirshekar, director of the Marine Ecosystems Office at the Department of Environment (DoE), said the presence of orcas (also known as killer whales) in the Persian Gulf is not unusual.

“This species was seen near the UAE a couple of weeks ago and then somewhere between (the Iranian islands of) Kish and Hendurabi,” the official said, according to Financial Tribune. Mirshekar noted that orcas have ventured into Iranian waters before but sightings were never reported.

“Their presence here is not strange at all. They’re here to feed,” he added.

The most widely distributed mammal, orcas have been documented foraging in shallow coastal waters.

In Iran, they are known by their less appealing name of killer whale, which sparked concerns among some people when the sightings were first reported.

“They pose no threats to humans,” Mirshekar said. “Their varied diet—from fish to seals—has garnered them the name of killer whale.”

The environment official said orcas are among the most intelligent animals on the planet, which is why they have historically had good relations with humans.

“There have only been a couple of reports of orcas attacking humans and they all happened when the animals were being held in captivity,” he said. Killer whales are commonly found swimming in the cold waters of Antarctic Peninsula, but a type known as Type B killer whales have been found to venture into the warmer waters of the tropics, such as the Persian Gulf, to help regenerate skin tissue.

They have been known to swim as far north as the states of Florida and Hawaii in the United States, so their sighting in the Persian Gulf—while infrequent—is not unusual.