The cars were stopping at a checkpoint on a ring road in Giza when the speeding truck drove into them, the broadcaster said, citing police sources.
Five others were injured in the accident, other Egyptian media reported. The truck driver was arrested.
On Tuesday, Egypt announced a two-week curfew in an effort to control the spread of the coronavirus, which has affected 456 people in the Arab world’s most populous country, resulting in 21 deaths.
The nationwide curfew went in effect on Wednesday from 7 pm (1700 GMT) to 6 am.
All public and private collective transportation are suspended during that time.
The Egyptian government has warned that violators would be liable to penalties, including imprisonment, under emergency law in force since 2017 after deadly church bombings.