The National Transport and Safety Authority has suspended the licence of the Modern Coast Bus Express Limited.
The move comes after the company's two buses were involved in an accident on Thursday, killing seven and injuring 62 people.
"Following the early Thursday morning crash involving two of their buses, the Authority has with immediate effect suspended the Company's operator's licence and initiated a thorough investigation into its safety standards and operations," NTSA said in a statement.
The authority said the company's access to the NTSA portal has been deactivated to limit any activities on their 88 vehicles, as the investigation continues.
"Over the last couple of days, the Authority has been monitoring the operations of Modern Coast Bus Express Limited following reports of several near-fatal crashes," the statement from Director General George Njao read.
The National Police has also been advised to impound any of their vehicles from operating contrary to this suspension.
The accident involved two Modern Coast buses at Kiongwani area near Salama market along the Nairobi-Mombasa Highway on Thursday morning.
Makueni County commander Joseph Napeiyan said the two buses headed in opposite directions collided head-on in the 2 am accident.
One bus was headed to Mombasa from Malaba while the other was headed to Nairobi from Mombasa.
A two-year-old baby is among those who lost their lives in the crash.
