The Belgian operation came hours after the prime minister, Charles Michel, announced reinforced security measures and a third day of lockdown in Brussels.
Hundreds of Central American migrants planning to seek asylum in the United States have reached the Mexican border city of Tijuana as the US military reinforced security measures, laying razor wire and erecting barricades.
"We are worried that there could be violence, and so we're reinforcing security measures," he said, adding that the police's role was to ensure a peaceful rally could go ahead.
"Bush, reinforce your security measures," the message said in Arabic.
The article quoted Mr. Zawahiri as saying on the tape, "Bush, reinforce your security measures" and "The Islamic nation which sent you the New York and Washington brigades has taken the firm decision to send you successive brigades to sow death and aspire to paradise".
The Foreign Ministry said it had asked all French diplomatic and consular posts in the region to reinforce their security measures to protect French citizens and that the French Navy was looking into ways to better protect French ships in the region.
Airbus emphasized that the incident was being investigated by its own experts who have "taken immediate and appropriate actions to reinforce existing security measures and to mitigate its potential impact, as well as determining its origins".
Mr Mignot points out that France had already reinforced its security measures well before the military deployed to Mali.
The Italian firm said it was bringing home its employees' families and non-essential personnel, and was "further reinforcing the security measures for its people and plants".
He later tweeted that he was heading to Barcelona and said the government would take measures to reinforce security.
French authorities had dispatched 120 police officers and that UK forces would be reinforcing the fences and upping security measures.
