Parts of a historic New York synagogue has been ordered to be vacated, after a secret tunnel constructed underneath it destabilised the sanctuary.
A fight erupted on Monday between police and community members who dug the tunnel after a cement truck arrived to fill it. Nine were arrested.
Officials said the tunnel, which was 60ft long, was not properly reinforced.
The city issued an emergency order to stabilise the structure on Wednesday.
"We have been on site in Crown Heights since [Tuesday] morning to investigate the illegal excavation work found underneath the buildings, and its impacts on the neighbouring structures," New York's Department of Buildings said.
"We will continue to monitor the progress of this emergency stabilization work," officials added, warning that additional action may be required.
City inspectors were called to the Chabad-Lubavitch headquarters in Brooklyn on Monday to conduct an emergency structural inspection under concerns that the illegal tunnel could have caused damage to the famous property.
A brawl then ensued between police and some men inside the synagogue resisting the effort.
They were charged with criminal mischief, reckless endangerment and obstructing governmental administration.
The tunnels were built under a prominent street in Brooklyn, where the Chabad-Lubavitch headquarters are located. The building is one of the most significant Jewish sites in the city.
The building, which sees thousands of visitors each year, was formerly the home of the leader of the Orthodox Jewish movement - Rabbi Menachem Mendel Schneerson.
The rabbi is credited with leading the Chabad-Lubavitch and revitalising the Hasidic religious community after it was devastated in the Holocaust. He died in 1994, but his headquarters remains a well-known centre for the Jewish religion.
It is unclear who built the tunnel, how they did it and what their motivations were. It appears the tunnel connects to at least one other building on the street in Brooklyn.
But a spokesperson for the Chabad blamed the incident on a "group of extremist students".
And Rabbi Yehuda Krinsky, the chairman of the Chabad, thanked police for their efforts and said the community was "pained by the vandalism of a group of young agitators".
"These odious actions will be investigated, and the sanctity of the synagogue will be restored," he said.
One local told the New York Times that the men sought to build the tunnel to hasten the expansion of the synagogue.
Some members who have attended services and functions at the Chabad have reportedly complained about overcrowding in the building in recent years.
