The US says it will not use a batch of Russian ventilators, pending inquiries into two deadly hospital fires.
The ventilators have been linked to blazes that killed five people in a coronavirus intensive care unit in St Petersburg on Tuesday, and one at a hospital in Moscow last week.
Russian regulators have suspended use of the Aventa-M ventilators nationwide, after they were linked to the fires.
The manufacturers say they have been in use since 2012 without safety concerns.
Radio-Electronic Technologies Concern, which controls the company that makes the Aventa-M, urged others not to rush to judgement until investigations had reported back.
What did US officials say?
In the US, the Federal Emergency Management Agency (Fema) made clear the Russian ventilators, procured during a race to stockpile medical equipment to deal with the coronavirus pandemic, had not been used.
The Aventa-M has "not been deployed to hospitals", Fema spokeswoman Janet Montesi said in a statement. "Out of an abundance of caution, the states are returning the ventilators to Fema."
The agency told CNBC: "The conclusion(s) of the investigation being conducted by the Russian authorities into the fire in St Petersburg will help inform our decision regarding any future use of the ventilators."
What happened in the fires?
The blaze at St George's Hospital in St Petersburg was apparently started by a short-circuit in a ventilator, Russian news agencies reported.
The fire was quickly put out and 150 people were evacuated from the hospital, the country's emergency ministry said. All the patients who died had been on ventilators.
"The ventilators are working to their limits. Preliminary indications are that it was overloaded and caught fire, and that was the cause," a source at St Petersburg emergencies department told the Interfax news agency.
Russia's NTV news website quoted doctors as saying a short-circuit caused a ventilator "literally to explode", and the ward filled with smoke, which suffocated the patients.
The fire did not spread beyond one small Covid-19 ward on the sixth floor.
A statement by Russia's healthcare watchdog Roszdravnadzor suggests ventilators are also suspected of causing a fire at Spasokukotsky hospital in Moscow on 9 May.
The Emergencies Ministry's Moscow branch reported that one person had died, and about 200 were evacuated. Reports said the blaze was in an intensive care ward, and had been started by ventilators. Part of the hospital was repurposed for treating Covid-19 patients in April.