PARIS -- French investigators are trying to identify a chemical applied to an electronic keypad at a Paris-area synagogue that burned more than a dozen congregants.
The Creteil prosecutor's office said Friday that analysis is still taking place on the substance, which caused light burns and eye irritation for the congregants at the synagogue in Bonneuil-sur-Marne late Monday. No one was hospitalized.
Jewish locations in France have been on high alert since the January attacks in Paris on a kosher supermarket and the Charlie Hebdo satirical newspaper.
Jewish communities around the world faced an "explosion of hatred" last year, with the number of violent anti-Semitic attacks rising by 38 percent, according to a report released by Israeli researchers.
The report by researchers at Tel Aviv University recorded 766 incidents - ranging from armed assaults to vandalism against synagogues, schools and cemeteries - compared to 554 in 2013.
According to CBS Radio News' Robert Berger, the report said most of the anti-Semitic incidents occurred in France.
"We're speaking about a change in environment in Europe, and Jewish life in Europe is at risk," said researcher Arie Zuckerman of the European Jewish Congress.
As in past years, the highest number of attacks was reported in France, which saw 164 incidents compared to 141 in 2013. In Britain there were 141 attacks, up from 95, and in the United States there were 80 incidents versus 55, including a shooting at Jewish sites in Overland Park, Kansas, that killed three people.
Some western European countries saw even greater increases, with the number of incidents more than doubling in Germany, Belgium, Austria and Sweden. The attacks also target individuals more frequently, with 306 cases involving people as victims, a 66 percent increase.