The votes to override are scheduled for this afternoon. An all-clear signal was broadcast in the Capitol shortly before 3:30 p.m.
The House will convene in five minutes, it was announced.
The governor was in Farmer City most of the morning for the funeral of State Trooper Ryan Albin. In a Facebook video post Monday, Rauner called the tax hike and budget bill "a repeat of the same policies that created this financial crisis". At least one of the 15 House Republicans who voted for the tax hike was not expected to be at the Capitol on Thursday.
The Illinois State Capitol was placed on lockdown for approximately two hours Thursday after a woman scattered a powdered substance in several locations in the building - including Gov. Bruce Rauner's office, officials said.
Rauner had earlier implored the General Assembly to sustain his vetoes of a $36 billion spending plan financed with a $5 billion income tax increase. Rauner rapidly vetoed it, only to have the Democratic-controlled Senate just as swiftly override him.
The governor also compared the income tax increase to a "two-by-four smacked across the forehead".