Latest Soyuz capsule leak prompts Russians to plan possible rescue of space station crew

Cause of puncture remains unclear as officials say damage continues to be assessed

Russia is considering a rescue" plan to send an empty spacecraft to the International Space Station (ISS) to bring home three stranded crew members after their Soyuz crew capsule sprang a leak while docked to the orbiting outpost.

Roscosmos and Nasa officials said at a news conference on Thursday they were continuing to investigate how the coolant line of the capsule's external radiator sustained a tiny puncture last week, just as two cosmonauts were preparing for a routine spacewalk.