Police have arrested a third suspect in connection with the fatal shootings of pregnant teenager Savanah Soto and her boyfriend in Texas.

San Antonio police announced Wednesday that they arrested the stepmother of a 19-year-old man who faces a capital murder charge in the deaths of Soto and 22-year-old Matthew Guerra, whose bodies were found last month inside a parked car.

The woman, 47, is charged with tampering with evidence, abuse of a corpse and altering, destroying or concealing evidence of a human corpse, police said.

The bodies of Soto and Guerra were found in his Kia Optima on Dec. 26, police said. An unborn child was also found deceased, police said. The vehicle had likely been at that location for several days, according to the authorities.

No additional suspects are being sought in the case, police said.

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