INTEGRAL observation of the blazar 3C454.3 in outburst

The blazar 3C 454.3 (z = 0.859) has been observed by INTEGRAL as a Target-of-Opportunity for 200 ks, starting on May 15, 2005, at 18 40 UT following the announcement of a bright state at various frequencies (see Balonek, VSNET Alert; Remillard, ATel 484; Trushkin et al., ATel 488). The source was clearly detected by the IBIS/ISGRI instrument in the 20-40 and 40-100 keV energy bands, with a significance of 20 and 15 sigma, respectively.