NEW : three people injured in fighting in Israel after Israeli teen 's funeral . Family buries slain teenager after funeral held at Jerusalem mosque . East Jerusalem tightens security around Jerusalem . Police investigating whether boy 's death in retaliation for killings of three Israeli teens .
NEW : More than 60 people injured in fighting in Jerusalem after Palestinian teen 's funeral . Family buries slain teenager after funeral held at East Jerusalem mosque . Israel tightens security around Jerusalem . Police investigating whether boy 's death in retaliation for killings of three Israeli teens .