Raccoon City Incident (Anderson)

The Raccoon City outbreak as portrayed in Resident Evil: Apocalypse lasted mere hours between the reopening of the Hive facility and the city's nuclear destruction.

Outbreak
The outbreak of the t-virus occurred shortly after the events of the Infection of the Hive, when Major Timothy Cain ordered The Hive to be reopened. The group in charge of this operation was not prepared for the mutated creatures contained within. Being unarmed, they were defenseless as zombies and lickers escaped the facility and head to the surface. It wasn't long before they began to attack the local population, infecting them, and thus spreading the infection at a monumental rate.

As the outbreak progressed, Umbrella Corporation begun evacuating civilians by means of checkpoints, to ensure that no contaminated people escaped. However, the virus quickly reached the checkpoint, forcing Cain to close the gates in order to prevent the virus from escaping the city. Due to the massive crowds, he was forced to use gunfire to force the population back, sealing the checkpoint, and the only exit from the city, for good.

With the only avenue of escape gone, the civilian population had little chance of survival. The overwhelming majority of the city's occupants were killed and reanimated.

While Umbrella knew that they could not contain the infection, they still sought to gain what they could from the debacle, and dispatched the Nemesis to test its battle efficency by pitting it against the S.T.A.R.S. team, which it dispatched with ease. Once that was accomplished, the Nemesis was directed to battle Alice, though the creature was eventually defeated by her, and subsequently killed in a helicopter crash.

As dawn rose the day after the infection began, Umbrella made their last move to contain the outbreak for good, dispatching a nuclear weapon to destroy the city. The bomb was sucessful, leveling the city to the ground, destroying the undead, and presumably, all evidence of Umbrella's deeds.

Aftermath
Though Umbrella was able to destroy the city, they were not successful in their goal of eliminating all witnesses who could discredit them, as Alice, L.J., Jill Valentine,Carlos Olivera, and Terri Morales survived the nuclear blast, and subsequently sought to expose what Umbrella had done. Though they were initially successful, Umbrella managed to discredit the evidence against them, once again ensuring that they would survive.

However, the victory was short lived, as despite their precautions, Umbrella failed to recognize that the virus had escaped the blast, incubating inside infected scientist Jim Knable, who had fled the city moments before it had been sealed off. With this catastrophic mistake, the virus survived, and began to spread far beyond the ruins of the wrecked metropolis, and began to infect the entire planet, leading to the Global T-virus Outbreak, which killed billions, and brought humanity to the edge of extinction.