An IndyCar official confirmed Wednesday morning to NBCSports.com that a testing ban has been instituted through May 10 for teams in the NTT Series.
The news was first reported Tuesday night by Racer.com.
There had been multiple tests scheduled in April, most notably an April 6 session at Barber Motorsports Park in which seven-time champion Jimmie Johnson was to have driven for Arrow McLaren SP. IndyCar also had planned tests at Indianapolis Motor Speedway (oval and road course) and Richmond Raceway.
Similar to a NASCAR ban that was enacted Tuesday, the IndyCar ban includes on-track manufacturer and private testing as well as wind tunnels and straight-line testing.
IndyCar announced last week that it has canceled or postponed its first four races through April. The 2020 season currently is scheduled to begin with the GMR Grand Prix on the Indianapolis Motor Speedway road course.
Indianapolis Motor Speedway released a statement Monday that it still is prepared to hold its events in May.
Scott Dixon was fastest on the second day of Indy 500 practice Thursday, turning a lap at 226.102 mph in his No. 9 Dallara-Honda at Indianapolis Motor Speedway.
Takuma Sato was second, followed by Marco Andretti, Conor Daly and rookie Alex Palou.
The rest of the top 10 were: Colton Herta, Charlie Kimball, James Hinchcliffe, Fernando Alonso and James Davison.
THURSDAY PRACTICE: Click here for Day 2 speeds at Indianapolis
COMBINED SPEEDS: Click here for the overall speeds from the first two days
The session had one incident as Alonso crashed with just less than an hour left in the session. The Arrow McLaren SP driver was optimistic that the car could be repaired without a backup.
Among the other notables on the speed chart Thursday: Ryan Hunter-Reay (11th); Tony Kanaan (14th); Helio Castroneves (16th); Josef Newgarden (18th); Graham Rahal (19th); Will Power (23rd); Alexander Rossi (26th) and defending race winner Simon Pagenaud (27th).
Felix Rosenqvist (24th) and rookie Dalton Kellett turned the most laps (141) around the 2.5-mile oval.
Teams mostly focused on race setup Thursday as they will receive 80 extra horsepower in the “Fast Friday” practice that will feature speeds above 230 mph for qualifying Saturday and Sunday.
The Indy 500 will take place Aug. 23; coverage begins at 1 p.m. ET on NBC with the green flag at 2:30 p.m.
HOW TO WATCH THE INDY 500 ON NBC: Details for the Aug. 23 race
DAILY INDY 500 SCHEDULE: Click here for all on-track activity in August at Indy