In 2017, when our whole country was shaken by acts of terrorism, the Jewish community was among the very first to stand with policing.

In London, within hours of the awful events on Westminster Bridge, the Chief Rabbi reached out, his support quickly mirrored in Tel Aviv with our flag displayed in solidarity at its city hall. And in Manchester, a local rabbi brought hot drinks to officers guarding the terrible scene at the Arena, speaking about the need to stand together, shoulder-to-shoulder, demonstrating acts of enduring kindness.

Today it is those of you in the Jewish community who need our support and our solidarity.

Nobody can fail to have been absolutely appalled by the acts of terrorism we saw in Israel on Saturday. The murder of more than 900 people and the kidnapping of so many others — including children and the elderly — must be condemned in the strongest terms.

We also understand that it has had a direct impact on people across the world, including right here in London, particularly those of you in our Jewish communities, including the Jewish officers and staff who work for the Met.

We stand firmly with you and we will do all that we can to make sure you feel safe and protected here at home.

I know that many families will today be grieving and fearful for their friends and relatives in Israel. It must be unimaginably painful to be so far away from people you are so close to at times like these. Please know you are in our minds and that we stand ready to support investigations and to help get Britons home if called on by the government to assist.

I know too that many people will be worried about their safety here, in London. Nobody should be concerned about their child’s journey to school, their safety on a bus or a train, their visit to the shops, or to a place of worship.

Working with community leaders and the Community Security Trust, we are increasing our presence at schools and synagogues and in communities. Our neighbourhood policing teams and dedicated schools officers will be there to provide assurance and support, but also to investigate and prosecute any instances of antisemitic hate or harassment.

I can also understand why, just days after such a barbaric terrorist attack, the sight of people gathering outside the Israeli Embassy, waving flags, chanting, letting off flares, some with scarves across their faces, will be interpreted by many of you as a direct statement of support for what took place on Saturday in Israel.

Many of you will no doubt find it morally reprehensible, intimidating, and even frightening and I can understand why there is an expectation that the police would have acted to stop the demonstration or to take action against those involved.

Hamas is a proscribed terrorist organisation under UK law. Hezbollah is too. Anyone who expresses support for these organisations, waves their flag, holds up a placard or directly expresses support for them is committing an offence and can expect to be dealt with.

The law on this is very clear, but it is also very specific and we have to act within it.

What we cannot do is interpret support for the Palestinian cause more broadly as automatically being support for Hamas or any other proscribed group, even when it follows so soon after an attack carried out by that group and when to many the link seems indisputable.

An expression of support for the Palestinian people more broadly, including flying the Palestinian flag, does not, alone, constitute a criminal offence.

Of course behaviour at protests goes beyond what is and isn’t seen as support for proscribed groups. I know that in the past we have seen people use these opportunities to make statements that are quite clearly antisemitic and a hate crime.

Abuse or intimidation that is religiously motivated will not be accepted and officers will act when they see it.

There are practical points on making arrests in the midst of thousands of people that call for judgments but we will step in, and have done so, to arrest those committing offences.

In the coming days and weeks there will no doubt be further challenges and further protests. We will police them without fear or favour and I expect our officers to act where they see offences, including expressions of support for proscribed organisations or any instance of religious hatred.

Please know those of us who joined policing to serve and protect find acts of violence, threats and kidnapping abhorrent.

I have heard the strength of feeling from many of you in the Jewish community. Our officers hear it too. We will act swiftly where people break the law and we will do everything in our power to protect you and to make you feel safe.

Lynne Owens is the deputy commissioner of the Metropolitan Police.