  We present multiwavelength analysis of an M7.9 /1N solar flare which occurred
on 27 April 2006 in AR NOAA 10875. The flare was triggered due to the
interaction of two loop systems. GOES soft X-ray and TRACE 195 {\AA} image
sequences show the observational evidences of 3-D X-type loop-loop interaction
with converging motion at the interaction site. We found the following
characteristics during the loop- loop interaction: (i) a short
duration/impulsive flare obeying the Neupart effect, (ii) double peak structure
in radio flux profiles (in 4.9 and 8.8 GHz), (iii) quasi-periodic oscillations
in the radio flux profiles for the duration of \sim3 min, (iv) absence of CME
and type III radio burst. The above characteristics observed during the flare
are in agreement with the theory and simulation of current loop coalescence by
Sakai et al. (1986). These are unique multiwavelength observations, which
provide the evidences of loop-loop interaction and associated triggering of
solar flare without CME.
