Suspicious powder envelope prompts FBI, hazmat response at downtown federal building

An envelope holding an unknown white powder was opened Friday afternoon inside the Mickey Leland Federal Building at 1919 Smith Street, which houses Sen. Ted Cruz's Houston office as well as the passport office and immigration court. Houston police said the call came in around 3:45 to 3:50 p.m., and HPD, a Houston Fire Department hazmat team, the FBI and postal inspectors responded. Sources told local stations the envelope was sent to Cruz's office, that the office was evacuated, and that staff are safe. Officials have not said what the substance is. The FBI says it is investigating a string of suspicious mailings sent to congressional and election offices around the country. Source: KHOU 11, KPRC 2, ABC13, FOX 26, Houston Chronicle