A testing centre in the Netherlands has been hit by an explosion in what police believe may be a targeted attack.
The explosion was just before 7am near the health service's testing centre in the town of Bovenkarspel, north of Amsterdam.
Police are investigating whether the attack, which shattered the building's windows, was deliberate.
"Something like that doesn't just happen by accident," police spokesman Menno Hartenberg told media.
Broadcaster NOS reported a metal pipe exploded outside the centre but that is yet to be confirmed.
This is not the first time a Covid-19 testing centre has been the target of an attack.
In January a testing centre was set on fire in the Dutch village of Urk as protests broke out over the start of an overnight curfew in the Netherlands intended to rein in the virus.
The nation's lockdown has continued to draw anger from residents, sparking violent riots across the country.
The Netherlands has more than 1 million Covid-19 cases and more than 15,600 deaths.
In a bid to slow the number of coronavirus cases, the Government introduced a national curfew in January, which has been extended to March 15.
Last week a Dutch court upheld a Government appeal against a lower court's order to scrap a controversial coronavirus curfew, saying the Cabinet had not overstepped its brief.
The ruling against the case brought by the Covid-sceptic group Virus Truth has limited impact as parliament already pushed through a law to support the curfew instituted on January 23.