  An experiment to search for double beta decay processes in 96Ru and 104Ru,
which are accompanied by gamma rays, has been realized in the underground Gran
Sasso National Laboratories of the I.N.F.N. (Italy). Ruthenium samples with
masses of about (0.5-0.7) kg were measured with the help of ultra-low
background high purity Ge gamma ray spectrometry. After 2162 h of data taking
the samples were deeply purified to reduce the internal contamination of 40K.
The last part of the data has been accumulated over 5479 h. New improved half
life limits on 2\beta+/\epsilon \beta+/2\epsilon\ processes in 96Ru have been
established on the level of 10^{20} yr, in particular for decays to the ground
state of 96Mo: T1/2(2\nu 2\beta+) > 1.4 10^{20} yr, T1/2(2\nu \epsilon\beta+) >
8.0 10^{19} yr and T1/2(0\nu 2K) > 1.0 10^{21} yr (all limits are at 90% C.L.).
The resonant neutrinoless double electron captures to the 2700.2 keV and 2712.7
keV excited states of 96Mo are restricted as: T1/2(0\nu KL) > 2.0 10^{20} yr
and T1/2(0\nu 2L) > 3.6 10^{20} yr, respectively. Various two neutrino and
neutrinoless 2\beta\ half lives of 96Ru have been estimated in the framework of
the QRPA approach. In addition, the T1/2 limit for 0\nu 2\beta- transitions of
104Ru to the first excited state of 104Pd has been set as > 6.5 10^{20} yr.
