Two Eastern European men have been arrested in connection with the explosion near Aisha Mosque in Walsall last month.
The 25-year-old and 22-year-old were arrested just before 3pm today.
Police are searching an area of Talbot Way in Small Heath and as a precaution homes have been evacuated.
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Monday will be misty with overcast skies bringing periods of mostly light rain or drizzle.
Largely cloudy and mild, with outbreaks of rain or drizzle in most places and extensive hill fog.
Further low cloud, mist and hill fog is expected with outbreaks of rain and drizzle throughout the night.