This report says
Two members of an al Qaeda cell connected to top terror master Abu Musab al-Zarqawi have been caught in Jordan with chemical weapons and poisonous gas for a planned attack that Jordanian officials say would have killed up to 20,000 people.
The officials told the London-based newspaper al-Hayat on Friday that the al Qaeda plotters planned to launch a WMD attack against a Jordanian Military Intelligence installation, the US embassy in Amman and a government building in the country.
According to the Israeli newspaper Maariv, the al Qaeda terrorists managed to smuggle three cars packed with explosives into Amman. Jordanian security forces found a chemical charge in one vehicle.
“The bomb, had it been detonated, could have affected people in a one kilometer radius and cause the deaths of up to 20,000 people,” Jordanian officials told Maariv
This plot was stopped on Monday.
Another Report says:
Jordan’s King Abdullah revealed on Saturday that vehicles reportedly containing chemical weapons and poison gas that were part of a deadly al Qaeda bomb plot came from Syria, the country named by U.S. weapons inspector David Kay last year as a likely repository for Iraq’s weapons of mass destruction.
I haven’t seen this story reported anywhere I looked in the blogosphere so far. I was surprised to not find it mentioned at Little Green Footballs and a Google News search only found the story I referenced. So if this is credible I am surprised at the lack of attention it has received thus far.