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We present the results from INTEGRAL and Swift/XRT observations of thehitherto poorly studied unidentified X-ray transient AX J1949.8+2534, and onarchival multiwavelength observations of field objects. Bright hard X-rayoutbursts have been discovered above 20 keV for the first time, the measuredduty cycle and dynamic range are of the order of 4% and >630, respectively. Thesource was also detected during a low soft X-ray state (2x10E-12 erg cmE-2sE-1) thanks to a Swift/XRT followup, which allowed for the first time toperform a soft X-ray spectral analysis as well as significantly improve thesource positional uncertainty from arcminute to arcsecond size. From archivalnear-infrared data, we pinpointed two bright objects as most likelycounterparts whose photometric properties are compatible with an early typespectral nature. This strongly supports a High Mass X-ray Binary (HMXB)scenario for AX J1949.8+2534, specifically a Supergiant Fast X-ray Transient(more likely) or alternatively a Be HMXB.

First hard X-ray detection and broad band X-ray study of the unidentified transient AX J1949.8+2534