	In response to the worsening security situation, William conducted his second northern campaign in 1069. He built another castle in York, on what is now Baile Hill on the west bank of the Ouse opposite the first castle, in an effort to improve his control over the city. This second castle was also a motte and bailey design, with the Baile Hill motte probably reached by a horizontal bridge and steps cut up the side of the motte. Later that year, a Danish Viking fleet sailed up to York along the Humber and the Ouse, and attacked both castles with the assistance of Cospatrick of Northumbria and a number of local rebels. The Normans, attempting to drive the rebels back, set fire to some of the city's houses. The fire grew out of control and also set fire to York Minster and, some argue, the castles as well. The castles were captured and partially dismantled, and Malet was taken hostage by the Danes.