Task: Question Answering
Input (English): Passage: Following the Denver Broncos loss on Thursday night to the San Diego Chargers, the Raiders looked to move into sole possession of first place in the AFC West as they hosted the Kansas City Chiefs. Things began well for the Raiders as Jalen Richard returned the opening kick 50 yards and Derek Carr hit Andre Holmes for a three-yard touchdown pass to put the Raiders up 7-0. However, the struggling Raiders defense continued to have problems stopping opponents as the Chiefs scored on a two-yard touchdown run by Spencer Ware and a four-yard run by Jamaal Charles (extra point failed), putting the Chiefs in front 13-7. The Raiders were able to get a field goal from Sebastian Janikowski as the half ended to pull within 13-10. However, Chiefs head coach Andy Reid, who is 16-2 in his career coming off of bye weeks, continued to baffle the Raiders defense in the second half. The Chiefs added a one-yard run by defensive lineman Dontari Poe and two field goals by Cairo Santos to go up 26-10. The Raiders offense managed nothing in the second half and the Chiefs won 26-10. The Chiefs offense put up 406 yards on the hapless Raiders defense. The Raiders fell to 4-2 on the season and back into a first place tie with the Broncos. 
Question: How many points were the Chiefs leading by at halftime? 
Answer type: Number 
Output (English): 6.