The 4, 5, 6, 7, A, C, D, E, F, L, Q and Times Square Shuttle are all affected.
More than 2,000 additional people could ride the L train per hour with the improvements, the MTA said.
The MTA does not have enough money to add an elevator to the Canarsie-bound platform.
The 25-year-old victim was mugged at the Atlantic Avenue station in Brownsville, police said.
The robbers made off with the victim's Phat Farm shoes, along with his wallet and two phones, NYPD said.
Fire spread to train tracks at East 105th Street and Farragut Road, officials said.
The L train resumed service following signal problems, the MTA said.
The 1, 2, 4, 5, 6, 7, E, F, G, L, N, Q, R and S lines will be affected by construction this weekend.
Police spotted Sidney Aime choking a woman inside the Union Square subway station, the NYPD said.
The change is to meet ridership demand, which is at an all-time high, according to the MTA.
Nearly half of all subway lines were dirtier in 2013 than they were in 2011, according to the survey.
Ridership at the First Avenue L train station spiked more than 10 percent from 2009 to 2012.
The disruption is caused by signal problems between Broadway Junction and Myrtle Ave.-Wycoff Ave.
The 4, 6, 7, A, C, D, F, J, L, M, N, Q, R, S and Staten Island Railway lines will all be affected.
Clients flocked to the corner off the L train for free cuts of all kinds.
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