NASA astronaut Terry Virts was quickly pulled into the International Space Station to remove him from his space suit yesterday after water pooled in his helmet. He was one of two astronauts taking part in an almost seven-hour spacewalk to begin preparing parking spots for new commercial space taxis.

It was not immediately clear what caused the water to appear in the helmet. A NASA commentator said there was no indication there was water intrusion during the spacewalk.

Italian astronaut Samantha Cristoforetti notified Mission Control of the water, and proceeded to pull him in.

"Houston, on one with a water in the helmet report. Yeah, Terry was saying he's got some water in his helmet. He just noticed it a minute ago. It's about three inches in diameter. It's kind of pooling on the front side of the helmet above his eye level," Cristoforetti said.

NASA said flight engineer Virts, 47, and station commander Barry "Butch" Wilmore, 52 were in no immediate danger.

The station, a partnership of 15 nations, is a collection of laboratories and platforms for materials and life science experiments, Earth studies, physics and other investigations that take advantage of the microgravity environment and unique vantage point of space.

The water issue was reminiscent of an incident in which water leaked into the helmet of Italian astronaut Luca Parmitano in 2013 during a spacewalk.