Mr Wiersum, 44, was the lawyer for a key witness in the prosecution of alleged gangsters accused of committing five murders between 2015 and 2017.

He was shot dead outside his home in Amsterdam on Wednesday morning while one of his two children was at home, the BBC reports. Police have not yet made any arrests.

In a statement, the CCBE said: “The murder of lawyers while exercising their professional duties is an unacceptable attack on the legal profession which role is essential to guarantee access to justice and protection of human rights and fundamental freedoms for all citizens - particularly through the protection of the rights of the defence and the guarantees of a fair trial.

“Attacks against lawyers are attacks against the rule of law.

“The CCBE will continue to fight to obtain that all lawyers are able to perform their professional duties without fear of reprisal, hindrance, intimidation or harassment, in order to preserve the independence and integrity of the administration of justice and the rule of law.”