One of the competitions would have been held in the village of Iten, where Tirop was found dead.
Agnes Tirop had two World Cup bronze medals on the merit list and a month ago set a world record for ten kilometers of road.
"As a union and individually, we condemn this heinous murder.
Nothing justifies taking someone's life.
Although the circumstances leading up to the assassination are unclear, this was unnecessary and a severe blow not only to the sports family but also to the local sports movement in which Tirop was one of the fastest growing stars, "the Kenyan Athletics Federation wrote in a statement.
Agnes Tirop turned 25 years old.