Strange Underground Noises in Derby

A few weeks ago the emergency services were called to Tennant Street in Derby, UK because members of the public heard a repetitive knocking and banging sound coming from beneath their feet. They could hear it emanating from below the pavement when they stood near manhole covers. The fire brigade managed to open one of the manholes where the noise was coming from the most but could see nothing untoward, or so they reported. They lacked the equipment and skills to carry out a more thorough investigation, and strangely no specialist unit appears to have attended in their wake. This response is made more suspicious because a passer-by told the local press that these noises have been recurring for quite a while, see: http://www.msn.com/en-gb/news/uknews/theres-something-in-the-sewers-mystery-as-tapping-noise-beneath-street-sparks-probe-by-police-and-fire-crew/ar-AAo25wm?li=BBoPWjQ. However a private inquiry was carried out by a local historian and paranormal researcher, Richard Felix. He discovered a network of mysterious tunnels under the street in 2009. Could there be a connection? Source: http://www.derbytelegraph.co.uk/could-derby-s-secret-underground-tunnels-be-linked-to-knocking-sound-in-tennant-street-near-quad/story-30191956-detail/story.html. I wonder if there might be a cryptozoological link as well, see: http://hpanwo-voice.blogspot.co.uk/2016/10/monster-in-sewer.html. Richard Felix was a speaker at the recent Paraforce UK 2016 where I also spoke, see: http://hpanwo-voice.blogspot.co.uk/2016/05/ben-emlyn-jones-live-at-paraforce-uk.html. (Apologies HPANWO Voice hasn't been updated for a few days. I've not had time)

See here for related stories: http://hpanwo-voice.blogspot.co.uk/2015/10/underground-city-discovered-in-mexico.html.

And: http://hpanwo-tv.blogspot.co.uk/2014/06/caves-under-nottingham.html.

And: http://hpanwo-voice.blogspot.co.uk/2014/08/gilmerton-cove.html.

And: http://hpanwo-voice.blogspot.co.uk/2013/12/mysterious-object-in-seattle-tunnel-dig.html.