We report on infrared observations of stars in a field of 30' near the
galactic centre. All these objects were previously detected as OH (16
12 MHz) maser sources. For a large fraction of these stars variability
data are available from a VLA monitor programme. This makes it possib
le to correct the IR measurements for variability. Corrections for int
erstellar extinction are also applied. The resulting infrared colours,
periods and luminosities are compared with results for other samples
of OH/IR stars and it is shown that the galactic centre stars are simi
lar to the same type of objects in the bulge of the Galaxy but that mo
re luminous (and thus younger) stars exist in the centre. The question
of the existence of two distinct populations of OH/IR stars near the
galactic centre is addressed, but the limited number of stars inhibits
a firm conclusion. We do find that when the sample is divided accordi
ng to OH expansion velocity, the dust-to-gas mass loss ratio, which de
pends on metallicity, is on average twice as high for the high expansi
on velocity group as for the low expansion velocity stars. The luminos
ities and the number density of the low expansion velocity stars are c
onsistent with them being an extension of the bulge population, wherea
s the high expansion velocity group contains brighter sources and is m
ore likely to be a population intrinsic to the galactic centre. The pr
eviously proposed period-luminosity (PL-) relation for OH/IR stars can
be studied with this sample. We find that the OH/IR stars significant
ly deviate from the PL-relation and argue that the OH/IR stars have ev
olved away from the PL-relation. It was found that non-variable OH/IR
stars are often associated with peculiar IR sources.