Two Canadian Jewish centers received bomb threats on Tuesday, reports The National Post.

In Toronto, toddlers and young children attending a daycare at the Miles Nadal Jewish Community Centre in the downtown area were evacuated after the center’s school received a robo-call of a bomb threat shortly after 10:00 a.m.

At almost the same time, the Jewish Community Centre of London, Ontario, located approximately halfway between Toronto and Detroit, received an identical threat. It was the second time that center has been threatened in two months, according to The Centre for Israel and Jewish Affairs (CIJA).

Police treated the threat in Toronto as credible and the center was searched. After the search did not find anything, the center reopened shortly before 1:00 p.m.

The threats in Canada happened as at least five Jewish community centers across the United States, a Jewish day school and a number of Anti-Defamation League offices received threats, the sixth such wave since the beginning of the year.

In Canada, according to The National Post, a Jewish community center in Calgary was evacuated February 27.

“These alarming incidents, combined with similar threats targeting Jewish community centers across North America, remind us of the need for continued vigilance in the fight against anti-Semitism,” CIJA said in a statement Tuesday.

Last week in Toronto, two swastikas were found drawn in chalk in a York University classroom. Police in York Region in Ontario later said they would increase patrols and presence at synagogues, Jewish community centers and other Jewish institutions across the region.