  In the last decades, the results from a number of short-baseline neutrino
experiments and the reanalysis of previous reactor experiments with updated
antineutrino fluxes suggest some incompatibility with the standard
three-neutrino model. A possible solution to these anomalies is the existence
of neutrinos that do not interact via the electroweak force, known as sterile
neutrinos. The existence of sterile neutrinos can be investigated with the T2K
Experiment. Here we present a search for the disappearance of electron
neutrinos over a baseline of 280 m using the T2K off-axis near detector. The
data analysed corresponds to an exposure of $5.9 \times 10^{20}$ protons on
target. The region $\sin^2 2 \theta > 0.2$ and $\Delta m^2 > 8~\textrm{eV}^2$
is excluded at 95% CL. We also present an introduction to a new analysis
looking for muon neutrino disappearance with the T2K near detector, which is in
its early stages but promises to have interesting results in 2015.
