Airstrikes hit rebel-held eastern Aleppo on Tuesday for the first time in three weeks, according to Syrian activists. The Britain-based Syrian Observatory for Human Rights voiced concern that the offensive could mean more fighting in the city. The strikes hit three neighborhoods, but officials had no updates on the number of casualties caused by the fighting. Activist Baraa al-Halaby said warplanes fired missiles and helicopters dropped barrel bombs. On Monday, residents of the area received a text message telling them to leave in advance of a “strategically planned assault using high-precision weapons” within 24 hours.