Northern German authorities are contacting thousands of people and informing them to get another COVID-19 jab after an investigation uncovered that a Red Cross nurse may have injected them with a saline solution.

The nurse has been suspected of injecting salt solution into people’s arms instead of a real dose at a vaccination centre in Friesland, a district near the North Sea Coast.

“I am totally shocked by this episode,” Sven Ambrosy, a local councillor, said on Facebook.

Local authorities are in the process of contacting over 8,600 residents who may have been affected.

Saline solution is harmless, however many people who got vaccinated in Germany in March and April are elderly people at high risk of catching the deadly viral disease.

Sadly, the time frame that a majority of elderly people received the jab, coincides with when the nurse is suspected to have switched the vaccines.

Police investigator Peter Beer, told German media that there is “a reasonable suspicion of danger”.

The nurse, who remains anonymous for now, made it clear on social media that she was sceptical of vaccines in social media posts, police investigators said.

This article first appeared on Over60.