JERUSALEM, Israel -- One of Iran's nuclear scientists was killed by a bomb Wednesday, the semi-official Iranian news agency Fars reported.
Mostafa Ahmadi Roshan, 32, was killed when two people on a motorcycle attached a magnetic explosive to his car.
Safar Ali Baratloo, a senior Iran security official, blamed Israel for the attack.
"The magnetic bomb is of the same types already used to assassinate our scientists," he said.
Several top Iranian nuclear scientists have been assassinated in recent years.
"Many bad things have been happening to Iran in the recent period," added Mickey Segal, a former director of the Israeli military's Iranian intelligence department.
"Iran is in a situation where pressure on it is mounting, and the latest assassination joins the pressure that the Iranian regime is facing," Segal added.
The news comes after Iran announced it has begun enriching uranium at an new underground facility in the near future.
Sunday's announcement increases the tension between Iran and Western nations trying to stop Tehran's nuclear program.
The Fordo facility, located near the Iranian city of Qom, is built into the side of a mountain that makes it a difficult military target.
"Even Israel's Defense Minister Ehud Barak has said it is immune to conventional military strikes," Yaakov Katz, military correspondent to the Jerusalem Post, told CBN News
Katz said the Fordo facility should alarm the West "because that would mean a further fortification of their uranium enrichment capability, something that's possibly immune to conventional military strike."
"Maybe there's another way to attack it - but it makes it all the more difficult and that means that time is closing, that the window of opportunity is closing," he warned.
The European Union will meet later in January and is expected to impose a ban on buying Iranian crude oil.
The move follows a U.S. law signed by President Obama on New Year's Eve to stop payments for Iranian oil.
The new sanctions seem to be having an impact on Iran's economy. The Islamic Republic's currency lost 20 percent of its value in the past week alone.