Yemeni officials said on Tuesday that the fighters seized control of the city, which is located about 72 kilometers (45 miles) north of the capital.
Mohammed Abdul-Salam, a Houthi spokesman, said the group did not mean to replace the government in the city and was only fighting extremist groups there.
The city has been the scene of fierce clashes between the fighters and government troops over the past days.
Many have been killed and thousands forced out of their homes due to the fighting.
Yemen’s Houthi movement draws its name from the tribe of its founding leader Hussein Badreddin al-Houthi.
The Houthi movement played a key role in the popular revolution that forced former dictator Ali Abdullah Saleh to step down.
Saleh, who ruled Yemen for 33 years, stepped down in February 2012 under a US-backed power transfer deal in return for immunity, after a year of mass street demonstrations demanding his ouster.
BA/BA