Mars Ajao, from Carmarthenshire in West Wales, said she had "shed many tears for the people caught up in this horrendous incident".
The auto continued along the footpath and the road before crashing into the perimeter fence of the Palace of Westminster, the statement from the London Metropolitan Police said.
Basu, who also serves as the UK's national coordinator for counter-terrorism, said the nature of Wednesday's attack - in which Masood ran over pedestrians on a London bridge before fatally stabbing a police officer - appeared to be based on "low-sophistication, low-tech, low-cost techniques copied from other attacks".
"There is no evidence that Masood was radicalised in prison in 2003, as has been suggested".
Police have said there was "no evidence" he had links with Islamic State or al Qaeda but was "clearly" interested in jihad.
He had a fairly extensive and violent criminal history, which spanned more than two decades, though he had not previously been convicted of terrorism-related activities.
Mr Basu said Masood's communications on March 22 were a "main line of inquiry" and appealed for people who were in contact with him to come forward.
Many of the Muslim women who showed up, some accompanied by their daughters, made a decision to participate following a social media backlash which occurred against an hijab-wearing woman whose photo was posted online in the midst of the attack. The victims of the attack included a 48-year-old unarmed police officer, Pc Keith Palmer and 43-year-old Spanish teacher Aysha Frade.
British officials have in recent days stepped up demands that technology companies enable intelligence services to access encrypted messages, with Home Secretary Amber Rudd saying there must be "no place for terrorists to hide".
A family living next door said Masood used to come wearing Islamic dress and take their neighbours' children to the mosque.
The investigation will entail breaking into his phone as WhatsApp is an "end-to-end" encryption messaging service. "Most importantly so do the victims and families".
"Yesterday we named the dead terrorist as Khalid Masood - we stated he had a number of aliases - we now know his birth name was Adrian Russell Ajao", Acting Deputy Commissioner Mark Rowley said at a press conference.
Earlier, the family of the United States tourist killed in the attack said he bore no ill will to anyone and spent his life "focusing on the positive".
Masood's victims included U.S. tourist Kurt Cochran and his wife Melissa who were on the last day of a trip celebrating their 25th wedding anniversary.
"The most hard part of all of this is that Kurt is no longer with us, and we miss him terribly".