US issues travel alert

People shop in a nearly empty arcade in the center of Brussels on Monday. (AP)

Washington – The United States issued a worldwide travel alert on Monday warning American citizens of “increased terrorist threats” in the wake of the Paris attacks.

Belgium’s prime minister announced on the same day that Brussels will remain at the highest alert level for at least another week, citing a “serious and imminent” threat of attack and the need to maintain security measures that have severely disrupted normal life in the capital.

In France, police said an explosive vest without a detonator was found by a street cleaner in a pile of rubble in the southern Paris suburb of Montrouge and was being analyzed by investigators. A police official said the vest contained bolts and the same type of explosives as those used in the Nov. 13 Paris attacks that claimed 130 lives and left hundreds wounded.

The device was found Monday in the same area where a cellphone belonging to fugitive suspect Salah Abdeslam was pinpointed by geolocalization on the day of the Paris attacks, two police officials said.

Belgian Prime Minister Charles Michel said Brussels, which houses the headquarters of the European Union and NATO, faced a “serious and imminent” threat that required keeping the city at the highest alert level, while the rest of the country would stay at the second-highest level. Belgium’s crisis center said the alert level would only change if a significant breakthrough warranted it.

The increased security measures in the wake of the Nov. 13 massacre in Paris have virtually shut down the Belgian capital, with the subway system, many shops and schools remaining shut on Monday. Michel said that despite the continued high alert level, schools would reopen on Wednesday, with parts of the subway system beginning to operate the same day.