Oct 28, 2013 8:11 PM by Associated Press
MESA (AP) - Authorities say a 16-year-old Mesa boy accused of killing his mother will be charged as an adult in the case.
Mesa police say the teen's 17-year-old friend also was booked into juvenile detention and is facing charges as an accomplice to the murder of 36-year-old Tina Helms Spencer.
Police say her body was found Saturday in a backyard shed at the family's property.
Authorities believe Spencer was struck with a frying pan and a hammer and also was choked.
Police say Spencer's son is being held on suspicion of first-degree murder, concealment of a dead body and tampering with evidence.
They say the boy admitted to planning the attack, but the motive remains unclear.
The names of the teens are being withheld by The Associated Press because they are juveniles.
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