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The ground state of interacting spin chains in external magnetic fields can undergo a quantum phase transition (QPT) characterized by dramatic changes at a critical value of the magnetic field. In this paper, we use Bell-type inequalities to study the multipartite correlations (including multipartite entanglement and multipartite nonlocality in an »-spin subsystem) in the QPT of an infinite XY chain. An efficient numerical optimization procedure is proposed to figure out the violation measure M„ of the inequalities. For n 7, the magnetic-field (À) dependence of M„ is studied. We find the derivative of M„ is divergent exactly at the QPT point Xc = 1 for any n. In addition, with the increase of n, M„ converges quickly for X < Xc and converges very slowly for X > Xc, which can be regarded as another signal for the QPT. Furthermore, in the vicinity of Xc, high-order Bell-type inequalities will be violated as long as n is large enough. This indicates that high-level multipartite correlation will be present when the system is in the vicinity of the QPT point. Nevertheless, genuine «-partite entanglement or genuine «-partite nonlocality is not observed in the QPT. [ABSTRACT FROM AUTHOR]