MERSEY tunnels today admitted emergency phones were not working when fire broke out.
Drivers claimed the lines were dead when they scrambled to alert authorities after ataxi burst into flames.
There was further chaos as motorists tried to flee the blaze during last Wednesday's evening rush hour with traffic queuing back into the Birkenhead tunnel because toll barriers remained down.
While saying lessons would be learned from the incident, tunnel managers insisted the phones were working and there was no record of anyone trying to use them.
But Merseytravel, which runs the tunnels, today admitted that phones were not connected.
A spokesman said: "There appears to have been a fault in the connection to the control room which we believe was down to human error.
"After testing, the telephones had not been switched through to the Wallasey control room. This is why we had no record of any attempts being made to use them.
"Normally if anyone picks up a telephone in the tunnels it is automatically logged.
"We apologise and please be assured that steps have been taken to ensure this cannot happen again.
"All other emergency procedures worked perfectly. Our control room spotted the taxi coming to a standstill in the tunnel but at that stage there was no smoke to indicate a fire."