[squid-users] assertion failed in cache.log

Hello All,
This morning my squid (2.4 stable 1) process seemed to die abnormally. When
i checked the cache.log it show me this message
assertion failed: refresh.c:163: "age >= 0"
What is the possible cause of this problem as the squid is behaving pretty
normally before today.
PS: running linux redhat 7.2

TIA

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