Exhausted and overworked, Horikoshi fell ill with pleurisy on 25 December and remained bedridden through early April. During this time, he recorded in detail the horrors of the increasing air raids on Tokyo and Nagoya, including the devastating "Operation Meetinghouse" Tokyo incendiary raid of 9–10 March. A massive air raid on Nagoya the following night, with B-29s hurling "tens of thousands of incendiary bombs," destroyed most of the largely wooden city. On 12 March, Horikoshi sent most of his family, including his elderly mother, children and brother-in-law, to his home village near Takasaki to be safe from the bombings, though his wife remained with him in Nagoya.